WARD, Circuit Judge.

This is an action under the federal Employers’ Diability Act (Comp. St. §§ 8657-8665) to recover damages for the death of Angelí Grimstad, captain of the covered barge Gray-ton, owned by the defendant railroad company. The charge of negligence is failure to equip the barge with proper life-preservers and other necessary and proper appliances, for want of which the decedent, having fallen into the water, was drowned.

The barge was lying on the port side of the steamer Santa Clara, on the north side of Pier 2, Erie Basin, Brooklyn, loaded with sugar in transit from Havana to St. John, N. B. The tug Mary M, entering the slip between Piers 1 and 2, bumped against the barge. The decedent’s wife, feeling the shock, came out from the cabin, looked on one side of the barge, and saw nothing, and then went across the deck to the other side, and discovered her husband in' the water about 10 feet from the barge holding up his hands out of the water. He did not know how to swim. She immediately ran back into the cabin for a small line, and when she returned with it he had disappeared.

It is admitted that the decedent at the time was engaged in inter*335state commerce. The court left it to the jury to say whether the defendant was negligent in not equipping the barge with life-preservers arid whether, if there had been a life-preserver on board, Grimstad would have been saved from drowning.

The jury found as a fact that the defendant was negligent in not equipping the barge with life-preservers. L,ife-preservers and life belts are intended to be put on the body of a person before getting into the water, and would have been of no use at all to the decedent. Qn the other hand, life buoys are intended to be thrown to a person when in the water, and we will treat the charge in the complaint as covering life buoys.

Obviously the proximate cause of the decedent’s death was his falling into the water, and in the absence of any testimony whatever on the point, we will assume that this happened without negligence on his part or on the part of the defendant. On the second question, whether a life buoy would have saved the decedent from drowning, we think the jury were left to pure conjecture and speculation. A jury might well conclude that a light near an open hatch or a rail on the side of a vessel’s deck would have prevented a person’s falling into the hatch or into the water, in the dark. But there is nothing whatever to show that the decedent was not drowned because he did not know how to swim, nor anything to show that, if there had been a life buoy on board, the decedent’s wife would have got it in time, that is, sooner than she got the small line, or, if she had, that she would have- thrown it so that her husband could have seized it, or, if she did, that he would have seized it, or that, if he did, it would have prevented him from drowning.

The court erred in denying the defendant’s motion to dismiss the complaint at the end of the case.

Judgment reversed.

Owen, J.

The jury found that both fires were set by sparks emitted from locomotives on and over defendant’s right of way. Appellant contends that there is no evidence to support the finding that either fire was so set. We' have carefully examined the record and have come to the conclusion that the evidence does support the finding that the northeast fire was set by sparks emitted from a locomotive then being rtm on and over the right of way of defendant’s main line. We conclude, however, that the evidence does not support the finding that the northwest fire was set by sparks *613emitted from defendant’s locomotives or that the defendant had any connection with its origin. A review of the evidence to justify these conclusions would seem to .serve no good purpose, and we content ourselves by a simple statement of the conclusions thus reached.

We therefore have this situation: The northeast fire was set by sparks emitted from defendant’s locomotive. This fire, according to the finding of the jury, constituted a proximate cause of the destruction of plaintiff’s property. This finding we find to be well supported- by the evidence. We have the northwest fire, of unknown origin. This fire, according to the finding of the jury, also constituted a proximate cause of the destruction of the plaintiff’s property. This finding we also find to be well supported by the evidence. We have a union of these two fires 940 feet north of plaintiff’s property,. from which point the united fire bore down upon and destroyed the property. We therefore have two separate, independent, and distinct agencies, each of which constituted the proximate-cause of plaintiff’s, damage, and either of which, in the absence of the other, would have accomplished such result.

It is settled in the law of negligence that' any one of two or more joint tortfeasors, or one of two or more wrongdoers whose concurring acts of negligence result in injury, are each individually responsible for the entire damage resulting from their joint or concurrent acts of negligence. This rule also obtains “where two causes, each attributable to the negligence of a responsible person, concur in producing an injury to another, either of which causes would produce it regardless of the other, . . . because, whether the concurrence be intentional, actual,, or constructive, each wrongdoer, in effect, adopts the conduct of his co-actor, and for the further reason that it is impossible to apportion the damage or to say that either perpetrated any distinct injury *614that can be separated from the whole. The whole loss must necessarily be considered and treated as an entirety.” Cook v. M., St. P. & S. S. M. R. Co. 98 Wis. 624 (74 N. W. 561), at p. 642. That case presented a situation very similar to this. One fire, originating by sparks emitted from a Iocoh motive, united with another fire of unknown origin and consumed plaintiffs’ property. There was nothing to indicate that the fire of unknown origin was not set by some human agency. The evidence in the case merely failed to identify the agency. In that case it was held that the railroad company which set one fire was not responsible for the damage committed by the united fires because the origin of the other fire was not identified. In that case a rule of law was announced, which is stated in the syllabus prepared by the writer of the opinion as follows:

“A fire started by defendant’s negligence, after spreading one mile and a quarter to the northeast, near plaintiffs’ property, met a fire having no responsible origin, coming from the northwest. After the -union, fire swept on from the northwest to and into plaintiffs’ property, causing its destruction. Either fire, if the other had not existed, would have reached the property and caused its destruction at- the same time. Held:

“(1) That the rule of liability in case of joint wrongdoers does not apply.

“(2) That the independent fire from the northwest became a superseding cause, so that the destruction of the property could not, with reasonable certainty, be attributed in whole or in part to the fire having a responsible origin; that the chain of responsible causation was so broken by the fire from the northwest that the negligent fire, if it reached the property at all, was a remote and not the proximate cause of the loss.”

Emphasis is placed upon the fact, especially in the opinion, that one fire had “no responsible origin.” At other times in the opinion the fact is emphasized that it had no “known *615responsible origin.” The plain inference from the entire opinion is that if both fires had been of responsible origin, or of known responsible origin, each wrongdoer would have been liable for the entire damage. The conclusion of the court exempting the railroad company from liability seems to be based upon the single fact that one fire had no responsible origin or no known responsible origin. It is difficult to determine just what weight was accorded to the fact that the origin of .the fire was unknown. If the conclusion of the court was founded upon the assumption that the fire of unknown origin had no responsible origin, the conclusion announced may be sound and in harmony with well settled principles of negligence.

From our present consideration of the subject we are not disposed to criticise the doctrine which exempts from liability a wrongdoer who sets a fire which unites with a fire originating from natural causes, such as lightning, not attributable to any human agency, resulting in damage. It is also conceivable that a fire so set might unite with a fire of so much greater proportions, such as a raging forest fire, as to be enveloped or swallowed up by the greater holocaust, and its identity destroyed, so- that the greater fire could be said to be an intervening or superseding cause. But we have no such situation here. These fires were of comparatively equal rank. If there was any difference in their magnitude or threatening aspect, the record indicates that the northeast fire was the larger fire and was really regarded as the menacing agency. At any rate there is no intimation or suggestion that the northeast fire was enveloped and swallowed up by the northwest fire. We will err on the side of the defendant if we regard the two fires as of equal rank.

According to well settled principles of negligence, it is undoubted that if the proof disclosed the origin of the northwest fire, even though its origin be attributed to a third per*616son, the railroad company, as the originator of the northeast fire, would be liable for the entire damage. There is no reason to believe that the northwest fire originated from any other than human agency; It was a small fire. It had traveled over a limited area. It had been in existence but for a day. For a time it was thought to have been extinguished. It was not in the nature of a raging forest fire. The record discloses nothing of natural phenomena which could have given rise to the fire. It is morally certain that it was set by some human agency.

Now the question is whether the railroad company, which is found to have been responsible for the origin of the northeast fire, escapes liability because the origin of the northwest fire is not identified, although there is no reason to believe that it had any other than human origin. An affirmative answer to that question would certainly make a wrongdoer a favorite of the law at the expense of an innocent sufferer. The injustice of such a doctrine sufficiently impeaches the logic upon which it is founded. Where one who has suffered damage by fire proves the origin of a fire and the course of that fire up to the point of the destruction of his property, one has certainly established liability on the part of the originator of the fire. Granting that the union of that fire with another of natural origin, or with another of much greater proportions, is available as a defense, the burden is on the defendant to show that by reason of such union with a fire of such character the fire set. by him was not the proximate cause of the damage. No principle of justice requires that the plaintiff be placed under the burden of specifically identifying the origin of both fires in order to recover' the damages for which either or both fires are responsible.

Speaking of the decision in the Cook Case, Thompson, in his work on Negligence, § 739, says:

“The conclusion is so clearly wrong as not to deserve discussion. It is just as though two wrongdoers, not acting in *617concert, or simultaneously, fire shots from different directions at the same person, each shot inflicting a mortal wound. Either wound being sufficient to cause death,'it would be'a childish casuistry that would engage in a debate as to which of the wrongdoers was innocent on the ground that the other was guilty.”

His illustration does not exactly answer the reason which we conceive to underlie the decision in the Cook Case. It would exactly fit it, as we understand the Cook Case, if the one who was known to have fired one of the shots should be permitted to escape liability for death because he who fired the other shot had not been identified, although it was certain that the other shot had been fired by some other human being. We are not disposed to apply the doctrine of the Cook Case to the instant situation. There being no attempt on the part of the defendant to prove that the northwest fire was due to an irresponsible origin, that is, an origin not attributable to a human being, and the evidence in the case affording no reason to believe that it had an origin not attributable to a human being, and it appearing that the northeast fire, for the origin of which the defendant is responsible, was a proximate cause of plaintiff’s loss, the defendant is responsible for the entire amount of that loss. While under some circumstances a wrongdoer is not responsible for damage which would have occurred in the absence of his wrongful act, even though such wrongful act was a proximate cause of the accident, .that doctrine does not obtain “where two causes, each attributable to the negligence of a responsible person, concur in producing an injury to another, either of which causes would produce it regardless of the other.” This is because “it is impossible to apportion the damage or to say that either perpetrated any distinct injury that can be separated from the whole,” and to permit each of two wrongdoers to plead the wrong of the other as a defense to his own wrongdoing would permit both *618wrongdoers to escape and penalize the innocent party who has been damaged by their wrongful acts.

The fact that the northeast fire was set by the railroad company, which fire was a proximate cause of plaintiff’s damage, is sufficient to affirm the judgment. This conclusion renders it unnecessary to consider other grounds of liability stressed in respondent’s brief.

By the Court. — Judgment affirmed.

CARTER, J.

Each of the two defendants appeals from a judgment against them in an action for personal injuries. Pursuant to stipulation the appeals have been consolidated.

Plaintiff’s action was against both defendants for an injury to his right eye and face as the result of being struck by bird shot discharged from a shotgun. The case was. tried by the court without a jury and the court found that on November 20, 1945, plaintiff and the two defendants were hunting quail on the open range. Each of the defendants was armed with a 12 gauge shotgun loaded with shells containing 7% size shot. Prior to going hunting plaintiff discussed the hunting procedure with defendants, indicating that they were to exercise care when shooting and to “keep in line.” In the course of hunting plaintiff proceeded up a hill, thus placing the hunters at the points of a triangle. The view of defendants with reference to plaintiff was unobstructed and they knew his location. Defendant Tice flushed a quail which rose in flight to a 10-foot elevation and flew between plaintiff and defendants. Both defendants shot at the quail, shooting in plaintiff’s direction. At that time defendants were 75 yards from plaintiff. One shot struck plaintiff in his eye and another in his upper lip. Finally it was found by the court that as *83the direct result of the shooting by defendants the shots struck plaintiff as above mentioned and that defendants were negligent in so shooting and plaintiff was not contributorily negligent.

First, on the subject of negligence, defendant Simon-son contends that the evidence is insufficient to sustain the finding on that score, but he does not point out wherein it is lacking. There is evidence that both defendants, at about the same time or one immediately after the other, shot at a quail and in so doing shot toward plaintiff who was uphill from them, and that they knew his location. That is sufficient from which the trial court could conclude that they acted with respect to plaintiff other than as persons of ordinary prudence. The issue was one of fact for the trial court. (See, Rudd v. Byrnes, 156 Cal. 636 [105 P. 957, 20 Ann.Cas. 124, 26 L.R.A. N.S.134].)

Defendant Tice states in his opening brief, “we have decided not to argue the insufficiency of negligence on the part of defendant Tice.” It is true he states in his answer to plaintiff’s petition for a hearing in this court that he did not concede this point but he does not argue it. Nothing more need be said on the subject.

Defendant Simonson urges that plaintiff was guilty of contributory negligence and assumed the risk as a matter of law. He cites no authority for the proposition that by going on a hunting party the various hunters assume the risk of negligence on the part of their companions. Such a tenet is not reasonable. It is true that plaintiff suggested that they all “stay in line,” presumably abreast, while hunting, and he went uphill at somewhat of a right angle to the hunting line, but he also cautioned that they use care, and defendants knew plaintiff’s position. We hold, therefore, that the trial court was justified in finding that he did not assume the risk or act other than as a person of ordinary prudence under the circumstances. (See, Anthony v. Hobbie, 25 Cal.2d 814, 818 [155 P.2d 826] ; Rudd v. Byrnes, supra.) None of the cases cited by Simonson are in point.

The problem presented in this case is whether the judgment against both defendants may stand. It is argued by defendants that they are not joint tort feasors, and thus jointly and severally liable, as they were not acting in concert, and that there is not sufficient evidence to show which defendant was guilty of the negligence which caused the injuries—the shooting by Tice or that by Simonson. Tice argues that there is *84evidence to show that the shot which struck plaintiff came from Simonson’s gun because of admissions allegedly made by him to third persons and no evidence that they came from his gun. Further in connection with the latter contention, the court failed to find on plaintiff’s allegation in his complaint that he did not know which one was at fault—did not find which defendant was guilty of the negligence which caused the injuries to plaintiff.

Considering the last argument first, we believe it is clear that the court sufficiently found on the issue that defendants were jointly liable and that thus the negligence of both was the cause of the injury or to that legal effect. It found that both defendants were negligent and “That as a direct and proximate result of the shots fired by defendants, and each of them, a birdshot pellet was caused to and did lodge in plaintiff’s right eye and that another birdshot pellet was caused to and did lodge in plaintiff’s upper lip.” In so doing the court evidently did not give credence to the admissions of Simonson to third persons that he fired the shots, which it was justified in doing. It thus determined that the negligence of both defendants was the legal cause of the injury—or that both were responsible. Implicit in such finding is the assumption that the court was unable to ascertain whether the shots were from the gun of one defendant or the other or one shot from each of them. The one shot that entered plaintiff’s eye was the major factor in assessing damages and that shot could not have come from the gun of both defendants. It was from one or the other only.

It has been held that where a group of persons are on a hunting party, or otherwise engaged in the use of firearms, and two of them are negligent in firing in the direction of a third person who is injured thereby, both of those so firing are liable for the- injury suffered by the third person, although the negligence of only one of them could have caused the injury. (Moore v. Foster, 182 Miss. 15 [180 So. 73]; Oliver v. Miles, 144 Miss. 852 [110 So. 666; 50 A.L.R. 357]; Reyher v. Mayne, 90 Colo. 586 [10 P.2d 1109]; Benson v. Ross, 143 Mich. 452 [106 N.W. 1120, 114 Am.St.Rep. 675].) The same rule has been applied in criminal cases (State v. Newberg, 129 Ore. 564 [278 P. 568, 63 A.L.R. 1225]), and both drivers have been held liable for the negligence of one where they engaged in a racing contest causing an injury to d third person (Saisa v. Lilja, 76 F.2d 380). These cases speak of the action of defendants as being in concert as the ground *85if decision, yet it would seem they are straining that concept and the more reasonable basis appears in Oliver v. Miles, supra. There two persons were hunting together. Both shot at some partridges and in so doing shot across the highway injuring plaintiff who was travelling on it. The court stated they were acting in concert and thus both were liable. The court then stated: “ We think that . . . each is liable for the resulting injury to the boy, although no one can say definitely who actually shot him. To hold otherwise would be to exonerate both from liability, although each was negligent, and the injury resulted from such negligence.” [Emphasis added.] (P. 668 [110 So.'].) It is said in the Restatement: “For harm resulting to a third person from the tortious conduct of another, a person is liable if he . . . (b) knows that the other’s conduct constitutes a breach of duty and gives substantial assistance or encouragement to the other so to conduct himself, or (c) gives substantial assistance to the other in accomplishing a tortious result and his own conduct, separately considered, constitutes a breach of duty to the third person.” (Rest., Torts, § 876(b) (c).) Under subsection (b) the example is given: “A and B are members of a hunting party. Each of them in the presence of the other shoots across a public road at an animal, this being negligent as to persons on the road. A hits the animal. B’s bullet strikes C, a traveler on the road. A is liable to C.” (Rest., Torts, § 876 (b), com., illus. 3.) An illustration given under subsection (c) is the same as above except the factor of both defendants shooting is missing and joint liability is not imposed. It is further said that: “If two forces are actively operating, one because of the actor’s negligence, the other not because of any misconduct on his part, and each of itself is sufficient to bring about harm to another, the actor’s negligence may be held by the jury to be a substantial factor in bringing it about.” (Rest., Torts, § 432.) Dean Wigmore has this to say: “When two or more persons by their acts are possibly the sole cause of a harm, or when two or more acts of the same person are possibly the sole cause, and the plaintiff has introduced evidence that the one of the two persons, or the one of the same person’s two acts, is culpable, then the defendant has the burden of proving that the other person, or his other act, was the sole cause of the harm, (b) ... The real reason for the rule that each joint tortfeasor is responsible for the whole damage is the practical unfairness of denying the injured person redress simply because he cannot prove how *86much damage each did, when it is certain that between them they did all; let them be the ones to apportion it among themselves. Since, then, the difficulty of proof is the reason, the rule should apply whenever the harm has plural causes, and not merely when they acted in conscious concert. ...” (Wigmore, Select Cases on the Law of Torts, § 153.) Similarly Professor Carpenter has said: “[Suppose] the case where A and B independently shoot at C and but one bullet touches C’s body. In such case, such proof as is ordinarily required that either A or B shot C, of course fails. It is suggested that there should be a relaxation of the proof required of the plaintiff . . . where the injury occurs as the result of one where more than one independent force is operating, and it is impossible to determine that the force set in operation by defendant did not in fact constitute a cause of the damage, and where it may have caused the damage, but the plaintiff is unable to establish that it was a cause.” (20 Cal.L.Rev. 406.)

When we consider the relative position of the parties and the results that would flow if plaintiff was required to pin the injury on one of the defendants only, a requirement that the burden of proof on that subject be shifted to defendants becomes manifest. They are both wrongdoers—both negligent toward plaintiff. They brought about a situation where the negligence of one of them injured the plaintiff, hence it should rest with them each to absolve himself if he can. The injured party has been placed by defendants in the unfair position of pointing to which defendant caused the harm. If one can escape the other may also and plaintiff is remediless. Ordinarily defendants are in a far better position to offer evidence' to determine which one caused the injury. This reasoning has recently found favor in this court. In a quite analogous situation this court held that a patient injured while unconscious on an operating table in a hospital could hold all or any of the persons who had any connection with the operation even though he could not select the particular acts by the particular person which led to his disability. (Ybarra v. Spangard, 25 Cal.2d 486 [154 P.2d 687, 162 A.L.R. 1258].) There the court was considering whether the patient could avail himself of res ipsa loquitur, rather than where the burden of proof lay, yet the effect of the decision is that plaintiff has made out a case when he has produced evidence which gives rise to an inference of negligence which was the proximate cause of the injury. It is up to *87defendants to explain the cause of the injury. It was there said: “If the doctrine is to continue to serve a useful purpose, we should not forget that ‘the particular force and justice of the rule, regarded as a presumption throwing upon the party charged the duty of producing evidence, consists in the circumstance that the chief evidence of the true cause, whether culpable or innocent, is practically accessible to him but inaccessible to the injured person.’ ” (P. 490.) Similarly in the instant case plaintiff is not able to establish which of defendants caused his injury.

The foregoing discussion disposes of the authorities cited by defendants such as Kraft v. Smith, 24 Cal.2d 124 [148 P.2d 23], and Hernandez v. Southern California Gas Co., 213 Cal. 384 [2 P.2d 360], stating the general rule that one defendant is not liable for the independent tort of the other defendant, or that ordinarily the plaintiff must show a causal connection between the negligence and the injury. There was an entire lack of such connection in the Hernandez ease and there were not several negligent defendants, one of whom must have caused the injury.

Defendants rely upon Christensen v. Los Angeles Electrical Supply Co., 112 Cal.App. 629 [297 P. 614], holding that a defendant is not liable where he negligently knocks down with his car a pedestrian and a third person then ran over the prostrate person. That involves the question of intervening cause which we do not have here. Moreover it is out of harmony with the current rule on that subject and was properly questioned in Hill v. Peres, 136 Cal.App. 132 [28 P.2d 946] (hearing in this Court denied), and must be deemed disapproved. (See, Mosley v. Arden Farms Co., 26 Cal. 2d 213 [157 P.2d 372, 158 A.L.R. 872]; Sawyer v. Southern California Gas Co., 206 Cal. 366 [274 P. 544]; 2 Cal.Jur. 10-Yr. Supp. Automobiles, § 349; 19 Cal.Jur. 570-572.)

Cases are cited for the proposition that where two or more tort feasors acting independently of each other cause an injury to plaintiff, they are not joint tort feasors and plaintiff must establish the portion of the damage caused by each, even though it is impossible to prove the portion of the injury caused by each. (See, Slater v. Pacific American Oil Co., 212 Cal. 648 [300 P. 31]; Miller v. Highland Ditch Co., 87 Cal. 430 [25 P. 550, 22 Am.St.Rep. 254]; People v. Gold Run D. & M. Co., 66 Cal. 138 [4 P. 1152, 56 Am.Rep. 80]; Wade v. Thorsen, 5 Cal.App.2d 706 [43 P.2d 592]; California O. Co. v. Riverside P. C. Co., 50 Cal.App. 522 [195 P. 694]; *88 City of Oakland v. Pacific Gas & E. Co., 47 Cal.App.2d 444 [118 P.2d 328].) In view of the foregoing discussion it is apparent that defendants in cases like the present one may be treated as liable on the same basis as joint tort feasors, and hence the last-cited cases are distinguishable inasmuch as they involve independent tort feasors.

In addition to that, however, it should be pointed out that the same reasons of policy and justice shift the burden to each of defendants to absolve himself if he can—relieving the wronged person of the duty of apportioning the injury to a particular defendant, apply here where we are concerned with whether plaintiff is required to supply evidence for the apportionment of damages. If defendants are independent tort feasors and thus each liable for the damage caused by him alone, and, at least, where the matter of apportionment is incapable of proof, the innocent wronged party should not be deprived of his right to redress. The wrongdoers should be left to work out between themselves any apportionment. (See, Colonial Ins. Co., v. Industrial Acc. Com., 29 Cal.2d 79 [172 P.2d 884].) Some of the cited cases refer to the difficulty of apportioning the burden of damages between the independent tort feasors, and say that where factually a correct division cannot be made, the trier of fact may make it the best it can, which would be more or less a guess, stressing the factor that the wrongdoers are not in a position to complain of uncertainty. (California O. Co. v. Riverside P. C. Co., supra.)

It is urged that plaintiff now has changed the theory of his case in claiming a concert of action; that he did not plead or prove such concert. From what has been said it is clear that there has been no change in theory. The joint liability, as well as the lack of knowledge as to which defendant was liable, was pleaded and the proof developed the ease under either theory. We have seen that for the reasons of policy discussed herein, the case is based upon the legal proposition that, under the circumstances here presented, each defendant is liable for the whole damage whether they are deemed to be acting in concert or independently.

The judgment is affirmed.

Gibson, C. J., Shenk, J., Edmonds, J., Traynor, J., Schauer, J., and Spence, J., concurred.

Appellant Tice’s petition for a rehearing was denied December 16, 1948.

Opinion

MOSK, J.

This case involves a complex problem both timely and significant: may a plaintiff, injured as the result of a drug administered to her mother during pregnancy, who knows the type of drug involved but cannot identify the manufacturer of the precise product, hold liable for her injuries a maker of a drug produced from an identical formula?

Plaintiff Judith Sindell brought an action against eleven drug companies and Does 1 through 100, on behalf of herself and other women similarly situated. The complaint alleges as follows:

Between 1941 and 1971, defendants were engaged in the business of manufacturing, promoting, and marketing diethylstilbesterol (DES), a drug which is a synthetic compound of the female hormone estrogen. The drug was administered to plaintiff’s mother and the mothers of the class she represents,1 for the purpose of preventing miscarriage. In 1947, the Food and Drug Administration authorized the marketing of DES as a miscarriage preventative, but only on an experimental basis, with a requirement that the drug contain a warning label to that effect.

*594DES may cause cancerous vaginal and cervical growths in the daughters exposed to it before birth, because their mothers took the drug during pregnancy. The form of cancer from which these daughters suffer is known as adenocarcinoma, and it manifests itself after a minimum latent period of 10 or 12 years. It is a fast-spreading and deadly disease, and radical surgery is required to prevent it from spreading. DES also causes adenosis, precancerous vaginal and cervical growths which may spread to other areas of the body. The treatment for adenosis is cauterization, surgery, or cryosurgery. Women who suffer from this condition must be monitored by biopsy or colposcopic examination twice a year, a painful and expensive procedure. Thousands of women whose mothers received DES during pregnancy are unaware of the effects of the drug.

In 1971, the Food and Drug Administration ordered defendants to cease marketing and promoting DES for the purpose of preventing miscarriages, and to warn physicians and the public that the drug should not be used by pregnant women because of the danger to their unborn children.

During the period defendants marketed DES, they knew or should have known that it was a carcinogenic substance, that there was a grave danger after varying periods of latency it would cause cancerous and precancerous growths in the daughters of the mothers who took it, and that it was ineffective to prevent miscarriage. Nevertheless, defendants continued to advertise and market the drug as a miscarriage preventative. They failed to test DES for efficacy and safety; the tests performed by others, upon which they relied, indicated that it was not safe or effective. In violation of the authorization of the Food and Drug Administration, defendants marketed DES on an unlimited basis rather than as an experimental drug, and they failed to warn of its potential danger.2

Because of defendants’ advertised assurances that DES was safe and effective to prevent miscarriage, plaintiff was exposed to the drug prior to her birth. She became aware of the danger from such exposure within one year of the time she filed her complaint. As a result of the DES ingested by her mother, plaintiff developed a malignant bladder *595tumor which was removed by surgery. She suffers from adenosis and must constantly be monitored by biopsy or colposcopy to insure early warning of further malignancy.

The first cause of action alleges that defendants were jointly and individually negligent in that they manufactured, marketed and promoted DES as a safe and efficacious drug to prevent miscarriage, without adequate testing or warning, and without monitoring or reporting its effects.

A separate cause of action alleges that defendants are jointly liable regardless of which particular brand of DES was ingested by plaintiff’s mother because defendants collaborated in marketing, promoting and testing the drug, relied upon each other’s tests, and adhered to an industry-wide safety standard. DES was produced from a common and mutually agreed upon formula as a fungible drug interchangeable with other brands of the same product; defendants knew or should have known that it was customary for doctors to prescribe the drug by its generic rather than its brand name and that pharmacists filled prescriptions from whatever brand of the drug happened to be in stock.

Other causes of action are based upon theories of strict liability, violation of express and implied warranties, false and fraudulent representations, misbranding of drugs in violation of federal law, conspiracy and “lack of consent.”

Each cause of action alleges that defendants are jointly liable because they acted in concert, on the basis of express and implied agreements, and in reliance upon and ratification and exploitation of each other’s testing and marketing methods.

Plaintiff seeks compensatory damages of $1 million and punitive damages of $10 million for herself. For the members of her class, she prays for equitable relief in the form of an order that defendants warn physicians and others of the danger of DES and the necessity of performing certain tests to determine the presence of disease caused by the drug, and that they establish free clinics in California to perform such tests.

Defendants demurred to the complaint. While the complaint did not expressly allege that plaintiff could not identify the manufacturer of the precise drug ingested by her mother, she stated in her points and au*596thorities in opposition to the demurrers filed by some of the defendants that she was unable to make the identification, and the trial court sustained the demurrers of these defendants without leave to amend on the ground that plaintiff did not and stated she could not identify which defendant had manufactured the drug responsible for her injuries. Thereupon, the court dismissed the action.3 This appeal involves only five of ten defendants named in the complaint.4

Plaintiff Maureen Rogers filed a complaint containing allegations generally similar to those made by Sindell. She seeks compensatory and punitive damages on her own behalf, and on behalf of a class described in substantially the same terms as in Sindell’s complaint, as well as equitable relief comparable to that sought by Sindell. The trial court sustained demurrers of E.R. Squibb & Sons, the Upjohn Company, and Rexall Drug Company.5 Subsequent to the dismissal of her action *597against these defendants, Rogers amended the complaint to allege that Eli Lilly and Company, one of the defendants named in her complaint, had manufactured the drug used by her mother. Although Sindell’s action and the present case have been consolidated on appeal, much of the discussion which follows will apply to Rogers only if she does not succeed in establishing that Eli Lilly and Company manufactured the DES taken by her mother. “Plaintiff” as used in this opinion refers to Sindell, and we discuss only the allegations of Sindell’s complaint.

This case is but one of a number filed throughout the country seeking to hold drug manufacturers liable for injuries allegedly resulting from DES prescribed to the plaintiffs’ mothers since 1947.6 According to a note in the Fordham Law Review, estimates of the number of women who took the drug during pregnancy range from IV2 million to 3 million. Hundreds, perhaps thousands, of the daughters of these women suffer from adenocarcinoma, and the incidence of vaginal adenosis among them is 30 to 90 percent. (Comment, DES and a Proposed Theory of Enterprise Liability (1978) 46 Fordham L.Rev. 963, 964-967 [hereafter Fordham Comment].) Most of the cases are still pending. With two exceptions,7 those that have been decided resulted in judgments in favor of the drug company defendants because of the failure of the plaintiffs to identify the manufacturer of the DES prescribed to their mothers.8 The same result was reached in a recent California case. (McCreery v. Eli Lilly & Co. (1978) 87 Cal.App.3d 77, 82-84 [150 Cal.Rptr. 730].) The present action is another attempt to overcome this obstacle to recovery.

We begin with the proposition that, as a general rule, the imposition of liability depends upon a showing by the plaintiff that his or her injuries were caused by the act of the defendant or by an instrumentality under the defendant’s control. The rule applies whether the injury *598resulted from an accidental event (e.g., Shunk v. Bosworth (6th Cir. 1964) 334 F.2d 309) or from the use of a defective product. (E.g., Wetzel v. Eaton Corporation (D.Minn. 1973) 62 F.R.D. 22, 29-30; Garcia v. Joseph Vince Co. (1978) 84 Cal.App.3d 868, 873-875 [148 Cal.Rptr. 843]; and see Annot. collection of cases in 51 A.L.R.3d 1344, 1351; 1 Hursh & Bailey, American Law of Products Liability (2d ed. 1974) p. 125.)

There are, however, exceptions to this rule. Plaintiff’s complaint suggests several bases upon which defendants may be held liable for her injuries even though she cannot demonstrate the name of the manufacturer which produced the DES actually taken by her mother. The first of these theories, classically illustrated by Summers v. Tice (1948) 33 Cal.2d 80 [199 P.2d 1, 5 A.L.R.2d 91], places the burden of proof of causation upon tortious defendants in certain circumstances. The second basis of liability emerging from the complaint is that defendants acted in concert to cause injury to plaintiff. There is a third and novel approach to the problem, sometimes called the theory of “enterprise liability,” but which we prefer to designate by the more accurate term of “industry-wide” liability,9 which might obviate the necessity for identifying the manufacturer of the injury-causing drug. We shall conclude that these doctrines, as previously interpreted, may not be applied to hold defendants liable under the allegations of this complaint. However, we shall propose and adopt a fourth basis for permitting the action to be tried, grounded upon an extension of the Summers doctrine.

I

Plaintiff places primary reliance upon cases which hold that if a party cannot identify which of two or more defendants caused an injury, the burden of proof may shift to the defendants to show that they were not responsible for the harm. This principle is sometimes referred to as the “alternative liability” theory.

The celebrated case of Summers v. Tice, supra, 33 Cal.2d 80, a unanimous opinion of this court, best exemplifies the rule. In Summers, the plaintiff was injured when two hunters negligently shot in his direction. It could not be determined which of them had fired the shot that *599actually caused the injury to the plaintiff’s eye, but both defendants were nevertheless held jointly and severally liable for the whole of the damages. We reasoned that both were wrongdoers, both were negligent toward the plaintiff, and that it would be unfair to require plaintiff to isolate the defendant responsible, because if the one pointed out were to escape liability, the other might also, and the plaintiff-victim would be shorn of any remedy.. In these circumstances, we held, the burden of proof shifted to the defendants, “each to absolve himself if he can.” (Id., p. 86.) We stated that under these or similar circumstances a defendant is ordinarily in a “far better position” to offer evidence to determine whether he or another defendant caused the injury.

In Summers, we relied upon Ybarra v. Spangard (1944) 25 Cal.2d 486 [154 P.2d 687, 162 A.L.R. 1258]. There, the plaintiff was injured while he was unconscious during the course of surgery. He sought damages against several doctors and a nurse who attended him while he was unconscious. We held that it would be unreasonable to require him to identify the particular defendant who had performed the alleged negligent act because he was unconscious at the time of the injury and the defendants exercised control over the instrumentalities which caused the harm. Therefore, under the doctrine of res ipsa loquitur, an inference of negligence arose that defendants were required to meet by explaining their conduct.10

The rule developed in Summers has been embodied in the Restatement of Torts. (Rest.2d Torts, § 433B, subd. (3).)11 Indeed, the Summers facts are used as an illustration (p. 447).

*600Defendants assert that these principles are inapplicable here. First, they insist that a predicate to shifting the burden of proof under Summers-Ybarra is that the defendants must have greater access to information regarding the cause of the injuries than the plaintiff, whereas in the present case the reverse appears.

Plaintiff does not claim that defendants are in a better position than she to identify the manufacturer of the drug taken by her mother or, indeed, that they have the ability to do so at all, but argues, rather, that Summers does not impose such a requirement as a condition to the shifting of the burden of proof. In this respect we believe plaintiff is correct.

In Summers, the circumstances of the accident themselves precluded an explanation of its cause. To be sure, Summers states that defendants are “[ojrdinarily.. .in a far better position to offer evidence to determine which one caused the injury” than a plaintiff (33 Cal.2d 80, at p. 86), but the decision does not determine that this “ordinary” situation was present. Neither the facts nor the language of the opinion indicate that the two defendants, simultaneously shooting in the same direction, were in a better position than the plaintiff to ascertain whose shot caused the injury. As the opinion acknowledges, it was impossible for the trial court to determine whether the shot which entered the plaintiff’s eye came from the gun of one defendant or the other. Nevertheless, burden of proof was shifted to the defendants.

Here, as in Summers, the circumstances of the injury appear to render identification of the manufacturer of the drug ingested by plaintiff’s mother impossible by either plaintiff or defendants, and it cannot reasonably be said that one is in a better position than the other to make the identification. Because many years elapsed between the time the drug was taken and the manifestation of plaintiff’s injuries she, and many other daughters of mothers who took DES, are unable to make such identification.12 Certainly there can be no implication that plaintiff *601is at fault in failing to do so—the event occurred while plaintiff was in útero, a generation ago.13

On the other hand, it cannot be said with assurance that defendants have the means to make the identification. In this connection, they point out that drug manufacturers ordinarily have no direct contact with the patients who take a drug prescribed by their doctors. Defendants sell to wholesalers, who in turn supply the product to physicians and pharmacies. Manufacturers do not maintain records of the persons who take the drugs they produce, and the selection of the medication is made by the physician rather than the manufacturer. Nor do we conclude that the absence of evidence on this subject is due to the fault of defendants. While it is alleged that they produced a defective product with delayed effects and without adequate warnings, the difficulty or impossibility of identification results primarily from the passage of time rather than from their allegedly negligent acts of failing to provide adequate warnings. Thus Haft v. Lone Palm Hotel (1970) 3 Cal.3d 756 [91 Cal.Rptr. 745, 478 P.2d 465], upon which plaintiff relies, is distinguishable.14

It is important to observe, however, that while defendants do not have means superior to plaintiff to identify the maker of the precise drug *602taken by her mother, they may in some instances be able to prove that they did not manufacture the injury-causing substance. In the present case, for example, one of the original defendants was dismissed from the action upon proof that it did not manufacture DES until after plaintiff was born.

Thus we conclude the fact defendants do not have greater access to information that might establish the identity of the manufacturer of the DES which injured plaintiff does not per se prevent application of the Summers rule.

Nevertheless, plaintiff may not prevail in her claim that the Summers rationale should be employed to fix the whole liability for her injuries upon defendants, at least as those principles have previously been applied.15 There is an important difference between the situation involved in Summers and the present case. There, all the parties who were or could have been responsible for the harm to the plaintiff were joined as defendants. Here, by contrast, there are approximately 200 drug companies which made DES, any of which might have manufactured the injury-producing drug.16

Defendants maintain that, while in Summers there was a 50 percent chance that one of the two defendants was responsible for the plaintiff’s injuries, here since any one of 200 companies which manufactured DES *603might have made the product that harmed plaintiff, there is no rational basis upon which to infer that any defendant in this action caused plaintiff’s injuries, nor even a reasonable possibility that they were responsible.17

These arguments are persuasive if we measure the chance that any one of the defendants supplied the injury-causing drug by the number of possible tortfeasors. In such a context, the possibility that any of the five defendants supplied the DES to plaintiff’s mother is so remote that it would be unfair to require each defendant to exonerate itself. There may be a substantial likelihood that none of the five defendants joined in the action made the DES which caused the injury, and that the offending producer not named would escape liability altogether. While we propose, infra, an adaptation of the rule in Summers which will substantially overcome these difficulties, defendants appear to be correct that the rule, as previously applied, cannot relieve plaintiff of the burden of proving the identity of the manufacturer which made the drug causing her injuries.18

II

The second principle upon which plaintiff relies is the so-called “concert of action” theory. Preliminarily, we briefly describe the procedure a drug manufacturer must follow before placing a drug on the market. Under federal law as it read prior to 1962, a new drug was defined as one “not generally recognized as.. .safe.” (§ 102, 76 Stat. 781 (Oct. 10, 1962).) Such a substance could be marketed only if a new drug applica*604tion had been filed with the Food and Drug Administration and had become “effective.”19 If the agency determined that a product was no longer a “new drug,” i.e., that it was “generally recognized as...safe,” (21 U.S.C.A. § 321(p)(l) it could be manufactured by any drug company without submitting an application to the agency. According to defendants, 123 new drug applications for DES had been approved by 1952, and in that year DES was declared not to be a “new drug,” thus allowing any manufacturer to produce it without prior testing and without submitting a new drug application to the Food and Drug Administration.

With this background we consider whether the complaint states a claim based upon “concert of action” among defendants. The elements of this doctrine are prescribed in section 876 of the Restatement Second of Torts. The section provides, “For harm resulting to a third person from the tortious conduct of another, one is subject to liability if he (a) does a tortious act in concert with the other or pursuant to a common design with him, or (b) knows that the other’s conduct constitutes a breach of duty and gives substantial assistance or encouragement to the other so to conduct himself, or (c) gives substantial assistance to the other in accomplishing a tortious result and his own conduct, separately considered, constitutes a breach of duty to the third person.” With respect to this doctrine, Prosser states that “those who, in pursuance of a common plan or design to commit a tortious act, actively take part in it, or further it by cooperation or request, or who lend aid or encouragement to the wrongdoer, or ratify and adopt his acts done for their benefit, are equally liable with him. [1Í] Express agreement is not necessary, and all that is required is that there be a tacit understanding. ...” (Prosser, Law of Torts (4th ed. 1971) § 46, p. 292.)

Plaintiff contends that her complaint states a cause of action under these principles. She alleges that defendants’ wrongful conduct “is the result of planned and concerted action, express and implied agreements, collaboration in, reliance upon, acquiescence in and ratification, exploitation and adoption of each other’s testing, marketing *605methods, lack of warnings... and other acts or omissions...” and that “acting individually and in concert, [defendants] promoted, approved, authorized, acquiesced in, and reaped profits from sales” of DES. These allegations, plaintiff claims, state a “tacit understanding” among defendants to commit a tortious act against her.

In our view, this litany of charges is insufficient to allege a cause of action under the rules stated above. The gravamen of the charge of concert is that defendants failed to adequately test the drug or to give sufficient warning of its dangers and that they relied upon the tests performed by one another and took advantage of each others’ promotional and marketing techniques. These allegations do not amount to a charge that there was a tacit understanding or a common plan among defendants to fail to conduct adequate tests or give sufficient warnings, and that they substantially aided and encouraged one another in these omissions.

The complaint charges also that defendants produced DES from a “common and mutually agreed upon formula,” allowing pharmacists to treat the drug as a “fungible commodity” and to fill prescriptions from whatever brand of DES they had on hand at the time. It is difficult to understand how these allegations can form the basis of a cause of action for wrongful conduct by defendants, acting in concert. The formula for DES is a scientific constant. It is set forth in the United States Pharmacopoeia, and any manufacturer producing that drug must, with exceptions not relevant here, utilize the formula set forth in that compendium. (21 U.S.C.A. § 351(b).)

What the complaint appears to charge is defendants’ parallel or imitative conduct in that they relied upon each others’ testing and promotion methods. But such conduct describes a common practice in industry: a producer avails himself of the experience and methods of others making the same or similar products. Application of the concept of concert of action to this situation would expand the doctrine far beyond its intended scope and would render virtually any manufacturer liable for the defective products of an entire industry, even if it could be demonstrated that the product which caused the injury was not made by the defendant.

None of the cases cited by plaintiff supports a conclusion that defendants may be held liable for concerted tortious acts. They involve *606conduct by a small number of individuals whose actions resulted in a tort against a single plaintiff, usually over a short span of time, and the defendant held liable was either a direct participant in the acts which caused damage,20 or encouraged and assisted the person who directly caused the injuries by participating in a joint activity.21

Orser v. George (1967) 252 Cal.App.2d 660 [60 Cal.Rptr. 708], upon which plaintiff primarily relies, is also distinguishable. There, three hunters negligently shot at a mudhen in decedent’s direction. Two of them shot alternately with the gun which released the bullet resulting in the fatal wound, and the third, using a different gun, fired alternately at the same target, shooting in the same line of fire, perhaps acting tortiously. It was held that there was a possibility the third hunter knew the conduct of the others was tortious toward the decedent and gave them substantial assistance and encouragement, and that it was also possible his conduct, separately considered, was a breach of duty toward decedent. Thus, the granting of summary judgment was reversed as to the third hunter.

The situation in Orser is similar to Agovino v. Kunze, supra, 181 Cal.App.2d 591, in which liability was imposed upon a participant in a drag race, rather than to the facts alleged in the present case. There is no allegation here that each defendant knew the other defendants’ conduct was tortious toward plaintiff, and that they assisted and encouraged one another to inadequately test DES and to provide inadequate warnings. Indeed, it seems dubious whether liability on the concert of action theory can be predicated upon substantial assistance and encouragement given by one alleged tortfeasor to another pursuant to a tacit understanding to fail to perform an act. Thus, there was no concert of action among defendants within the meaning of that doctrine.

*607III

A third theory upon which plaintiff relies is the concept of industry-wide liability, or according to the terminology of the parties, “enterprise liability.” This theory was suggested in Hall v. E. I. Du Pont de Nemours & Co., Inc. (E.D.N.Y. 1972) 345 F.Supp. 353. In that case, plaintiffs were 13 children injured by the explosion of blasting caps in 12 separate incidents which occurred in 10 different states between 1955 and 1959. The defendants were six blasting cap manufacturers, comprising virtually the entire blasting cap industry in the United States, and their trade association. There were, however, a number of Canadian blasting cap manufacturers which could have supplied the caps. The gravamen of the complaint was that the practice of the industry of omitting a warning on individual blasting caps and of failing to take other safety measures created an unreasonable risk of harm, resulting in the plaintiffs’ injuries. The complaint did not identify a particular manufacturer of a cap which caused a particular injury.22

The court reasoned as follows: there was evidence that defendants, acting independently, had adhered to an industry-wide standard with regard to the safety features of blasting caps, that they had in effect delegated some functions of safety investigation and design, such as la-belling, to their trade association, and that there was industry-wide cooperation in the manufacture and design of blasting caps. In these circumstances, the evidence supported a conclusion that all the defen*608dants jointly controlled the risk. Thus, if plaintiffs could establish by a preponderance of the evidence that the caps were manufactured by one of the defendants, the burden of proof as to causation would shift to all the defendants. The court noted that this theory of liability applied to industries composed of a small number of units, and that what would be fair and reasonable with regard to an industry of five or ten producers might be manifestly unreasonable if applied to a decentralized industry composed of countless small producers.23

Plaintiff attempts to state a cause of action under the rationale of Hall. She alleges joint enterprise and collaboration among defendants in the production, marketing, promotion and testing of DES, and “concerted promulgation and adherence to industry-wide testing, safety, warning and efficacy standards” for the drug. We have concluded above that allegations that defendants relied upon one another’s testing and promotion methods do not state a cause of action for concerted conduct to commit a tortious act. Under the theory of industry-wide liability, however, each manufacturer could be liable for all injuries caused by DES by virtue of adherence to an industry-wide standard of safety.

In the Fordham Comment, the industry-wide theory of liability is discussed and refined in the context of its applicability to actions alleging injuries resulting from DES. The author explains causation under that theory as follows, “.. . [T]he industrywide standard becomes itself the cause of plaintiff’s injury, just as defendants’ joint plan is the cause of injury in the traditional concert of action plea. Each defendant’s adherence perpetuates this standard, which results in the manufacture of the particular, unidentifiable injury-producing product. Therefore, each industry member has contributed to plaintiff’s injury.” (Fordham Comment, supra, at p. 997.)

The comment proposes seven requirements for a cause of action based upon industry-wide liability,24 and suggests that if a plaintiff *609proves these elements, the burden of proof of causation should be shifted to the defendants, who may exonerate themselves only by showing that their product could not have caused the injury.25

We decline to apply this theory in the present case. At least 200 manufacturers produced DES; Hall, which involved 6 manufacturers representing the entire blasting cap industry in the United States, cautioned against application of the doctrine espoused therein to a large number of producers. (345 F.Supp. at p. 378.) Moreover, in Hall, the conclusion that the defendants jointly controlled the risk was based upon allegations that they had delegated some functions relating to safety to a trade association. There are no such allegations here, and we have concluded above that plaintiff has failed to allege liability on a concert of action theory.

Equally important, the drug industry is closely regulated by the Food and Drug Administration, which actively controls the testing and manufacture of drugs and the method by which they are marketed, including the contents of warning labels.26 To a considerable degree, therefore, the standards followed by drug manufacturers are suggested or compelled by the government. Adherence to those standards cannot, of course, absolve a manufacturer of liability to which it would otherwise be subject. (Stevens v. Parke, Davis & Co. (1973) 9 Cal.3d 51, 65 [107 *610Cal.Rptr. 45, 507 P.2d 653, 94 A.L.R.3d 1059].) But since the government plays such a pervasive role in formulating the criteria for the testing and marketing of drugs, it would be unfair to impose upon a manufacturer liability for injuries resulting from the use of a drug which it did not supply simply because it followed the standards of the industry.27

IV

If we were confined to the theories of Summers and Hall, we would be constrained to hold that the judgment must be sustained. Should we require that plaintiff identify the manufacturer which supplied the DES used by her mother or that all DES manufacturers be joined in the action, she would effectively be precluded from any recovery. As defendants candidly admit, there is little likelihood that all the manufacturers who made DES at the time in question are still in business or that they are subject to the jurisdiction of the California courts. There are, however, forceful arguments in favor of holding that plaintiff has a cause of action.

In our contemporary complex industrialized society, advances in science and technology create fungible goods which may harm consumers and which cannot be traced to any specific producer. The response of the courts can be either to adhere rigidly to prior doctrine, denying recovery to those injured by such products, or to fashion remedies to meet these changing needs. Just as Justice Tray nor in his landmark concurring opinion in Escola v. Coca Cola Bottling Co. (1944) 24 Cal.2d 453, 467-468 [150 P.2d 436], recognized that in an era of mass production and complex marketing methods the traditional standard of negligence was insufficient to govern the obligations of manufacturer to consumer, so should we acknowledge that some adaptation of the rules of causation and liability may be appropriate in these recurring circumstances. The Restatement comments that modification of the Summers rule may be necessary in a situation like that before us. (See fn. 16, ante.)

The most persuasive reason for finding plaintiff states a cause of action is that advanced in Summers: as between an innocent plaintiff and *611negligent defendants, the latter should bear the cost of the injury. Here, as in Summers, plaintiff is not at fault in failing to provide evidence of causation, and although the absence of such evidence is not attributable to the defendants either, their conduct in marketing a drug the effects of which are delayed for many years played a significant role in creating the unavailability of proof.

From a broader policy standpoint, defendants are better able to bear the cost of injury resulting from the manufacture of a defective product. As was said by Justice Traynor in Escola, “[t]he cost of an injury and the loss of time or health may be an overwhelming misfortune to the person injured, and a needless one, for the risk of injury can be insured by the manufacturer and distributed among the public as a cost of doing business.” (24 Cal.2d p. 462; see also Rest.2d Torts, § 402A, com. c, pp. 349-350.) The manufacturer is in the best position to discover and guard against defects in its products and to warn of harmful effects; thus, holding it liable for defects and failure to warn of harmful effects will provide an incentive to product safety. (Cronin v. J.B.E. Olson Corp. (1972) 8 Cal.3d 121, 129 [104 Cal.Rptr. 433, 501 P.2d 1153]; Beech Aircraft Corp. v. Superior Court (1976) 61 Cal.App.3d 501, 522-523 [132 Cal.Rptr. 541].) These considerations are particularly significant where medication is involved, for the consumer is virtually helpless to protect himself from serious, sometimes permanent, sometimes fatal, injuries caused by deleterious drugs.

Where, as here, all defendants produced a drug from an identical formula and the manufacturer of the DES which caused plaintiff’s injuries cannot be identified through no fault of plaintiff, a modification of the rule of Summers is warranted. As we have seen, an undiluted Summers rationale is inappropriate to shift the burden of proof of causation to defendants because if we measure the chance that any particular manufacturer supplied the injury-causing product by the number of producers of DES, there is a possibility that none of the five defendants in this case produced the offending substance and that the responsible manufacturer, not named in the action, will escape liability.

But we approach the issue of causation from a different perspective: we hold it to be reasonable in the present context to measure the likelihood that any of the defendants supplied the product which allegedly injured plaintiff by the percentage which the DES sold by each of them for the purpose of preventing miscarriage bears to the entire production *612of the drug sold by all for that purpose. Plaintiff asserts in her briefs that Eli Lilly and Company and five or six other companies produced 90 percent of the DES marketed. If at trial this is established to be the fact, then there is a corresponding likelihood that this comparative handful of producers manufactured the DES which caused plaintiff’s injuries, and only a 10 percent likelihood that the offending producer would escape liability.28

If plaintiff joins in the action the manufacturers of a substantial share of the DES which her mother might have taken, the injustice of shifting the burden of proof to defendants to demonstrate that they could not have made the substance which injured plaintiff is significantly diminished. While 75 to 80 percent of the market is suggested as the requirement by the Fordham Comment (at p. 996), we hold only that a substantial percentage is required.

The presence in the action of a substantial share of the appropriate market also provides a ready means to apportion damages among the defendants. Each defendant will be held liable for the proportion of the judgment represented by its share of that market unless it demonstrates that it could not have made the product which caused plaintiff’s injuries. In the present case, as we have seen, one DES manufacturer was dismissed from the action upon filing a declaration that it had not manufactured DES until after plaintiff was born. Once plaintiff has met her burden of joining the required defendants, they in turn may cross-complain against other DES manufacturers, not joined in the action, which they can allege might have supplied the injury-causing product.

Under this approach, each manufacturer’s liability would approximate its responsibility for the injuries caused by its own products. Some minor discrepancy in the correlation between market share and liability is inevitable; therefore, a defendant may be held liable for a somewhat different percentage of the damage than its share of the appropriate *613market would justify. It is probably impossible, with the passage of time, to determine market share with mathematical exactitude. But just as a jury cannot be expected to determine the precise relationship between fault and liability in applying the doctrine of comparative fault (Li v. Yellow Cab Co. (1975) 13 Cal.3d 804 [119 Cal.Rptr. 858, 532 P.2d 1226, 78 A.L.R.3d 393]) or partial indemnity (American Motorcycle Assn. v. Superior Court (1978) 20 Cal.3d 578 [146 Cal.Rptr. 182, 578 P.2d 899]), the difficulty of apportioning damages among the defendant producers in exact relation to their market share does not seriously militate against the rule we adopt. As we said in Summers with regard to the liability of independent tortfeasors, where a correct division of liability cannot be made “the trier of fact may make it the best it can.” (33 Cal.2d at p. 88.)

We are not unmindful of the practical problems involved in defining the market and determining market share,29 but these are largely matters of proof which properly cannot be determined at the pleading stage of these proceedings. Defendants urge that it would be both unfair and contrary to public policy to hold them liable for plaintiffs injuries in the absence of proof that one of them supplied the drug responsible for the damage. Most of their arguments, however, are based upon the assumption that one manufacturer would be held responsible for the products of another or for those of all other manufacturers if plaintiff ultimately prevails. But under the rule we adopt, each manufacturer’s liability for an injury would be approximately equivalent to the damage caused by the DES it manufactured.30

The judgments are reversed.

Bird, C. J., Newman, J., and White, J.,* concurred.

*614RICHARDSON, J.

I respectfully dissent. In these consolidated cases the majority adopts a wholly new theory which contains these ingredients: The plaintiffs were not alive at the time of the commission of the tortious acts. They sue a generation later. They are permitted to receive substantial damages from multiple defendants without any proof that any defendant caused or even probably caused plaintiffs’ injuries.

Although the majority purports to change only the required burden of proof by shifting it from plaintiffs to defendants, the effect of its holding is to guarantee that plaintiffs will prevail on the causation issue because defendants are no more capable of disproving factual causation than plaintiffs are of proving it. “Market share” liability thus represents a new high water mark in tort law. The ramifications seem almost limitless, a fact which prompted one recent commentator, in criticizing a substantially identical theory, to conclude that “Elimination of the burden of proof as to identification [of the manufacturer whose drug injured plaintiff] would impose a liability which would exceed absolute liability.” (Coggins, Industry-Wide Liability (1979) 13 Suffolk L.Rev. 980, 998, fn. omitted; see also, pp. 1000-1001.) In my view, the majority’s departure from traditional tort doctrine is unwise.

The applicable principles of causation are very well established. A leading torts scholar, Dean Prosser, has authoritatively put it this way: “An essential element of the plaintiff’s cause of action for negligence, or for that matter for any other tort, is that there be some reasonable connection between the act or omission of the defendant and the damage which the plaintiff has suffered.” (Prosser, Torts (4th ed. 1971) § 41, p. 236, italics added.) With particular reference to the matter before us, and in the context of products liability, the requirement of a causation element has been recognized as equally fundamental. “It is clear that any holding that a producer, manufacturer, seller, or a person in a similar position, is liable for injury caused by a particular product, must necessarily be predicated upon proof that the product in question was one for whose condition the defendant was in some way responsible. Thus, for example, if recovery is sought from a manufacturer, it must be shown that he actually was the manufacturer of the product which caused the injury;...” (1 Hursh & Bailey, American Law of Products Liability (2d ed. 1974) § 1:41, p. 125, italics added; accord, Prosser, supra, § 103, at pp. 671-672; 2 Dooley, Modern Tort Law (1977) § 32.03, p. 243.) Indeed, an inability to prove this causal link between defendant’s conduct and plaintiffs injury has proven fatal in prior cases *615brought against manufacturers of DES by persons who were situated in positions identical to those of plaintiffs herein. (See McCreery v. Eli Lilly & Co. (1978) 87 Cal.App.3d 77, 82 [150 Cal.Rptr. 730]; Gray v. United States (S.D.Tex. 1978) 445 F.Supp. 337, 338.)

The majority now expressly abandons the foregoing traditional requirement of some causal connection between defendants’ act and plaintiffs’ injury in the creation of its new modified industry-wide tort. Conceptually, the doctrine of absolute liability which heretofore in negligence law has substituted only for the requirement of a breach of defendant’s duty of care, under the majority’s hand now subsumes the additional necessity of a causal relationship.

According to the majority, in the present case plaintiffs have openly conceded that they are unable to identify the particular entity which manufactured the drug consumed by their mothers. In fact, plaintiffs have joined only five of the approximately two hundred drug companies which manufactured DES. Thus, the case constitutes far more than a mere factual variant upon the theme composed in Summers v. Tice (1948) 33 Cal.2d 80 [199 P.2d 1], wherein plaintiff joined as codefendants the only two persons who could have injured him. As the majority must acknowledge, our Summers rule applies only to cases in which “... it is proved that harm has been caused to the plaintiff by... one of [the named defendants], but there is uncertainty as to which one has caused it,... ” (Rest.2d Torts, § 433B, subd. (3).) In the present case, in stark contrast, it remains wholly speculative and conjectural whether any of the five named defendants actually caused plaintiffs’ injuries.

The fact that plaintiffs cannot tie defendants to the injury-producing drug does not trouble the majority for it declares that the Summers requirement of proof of actual causation by a named defendant is satisfied by a joinder of those defendants who have together manufactured “a substantial percentage” of the DES which has been marketed. Notably lacking from the majority’s expression of its new rule, unfortunately, is any definition or guidance as to what should constitute a “substantial” share of the relevant market. The issue is entirely open-ended and the answer, presumably, is anyone’s guess.

Much more significant, however, is the consequence of this unprecedented extension of liability. Recovery is permitted from a handful of defendants each of whom individually may account for a comparatively *616small share of the relevant market, so long as the aggregate business of those who have been sued is deemed “substantial.” In other words, a particular defendant may be held proportionately liable even though mathematically it is much more likely than not that it played no role whatever in causing plaintiffs’ injuries. Plaintiffs have strikingly capsulated their reasoning by insisting “.. . that while one manufacturer’s product may not have injured a particular plaintiff, we can assume that it injured a different plaintiff and all we are talking about is a mere matching of plaintiffs and defendants.” (Counsel’s letter (Oct. 16, 1979) p. 3.) In adopting the foregoing rationale the majority rejects over 100 years of tort law which required that before tort liability was imposed a “matching” of defendant’s conduct and plaintiff’s injury was absolutely essential. Furthermore, in bestowing on plaintiffs this new largess the majority sprinkles the rain of liability upon all the joined defendants alike—those who may be tortfeasors and those who may have had nothing at all to do with plaintiffs’ injury—and an added bonus is conferred. Plaintiffs are free to pick and choose their targets.

The “market share” thesis may be paraphrased. Plaintiffs have been hurt by someone who made DES. Because of the lapse of time no one can prove who made it. Perhaps it was not the named defendants who made it, but they did make some. Although DES was apparently safe at the time it was used, it was subsequently proven unsafe as to some daughters of some users. Plaintiffs have suffered injury and defendants are wealthy. There should be a remedy. Strict products liability is unavailable because the element of causation is lacking. Strike that requirement and label what remains “alternative” liability, “industry-wide” liability, or “market share” liability, proving thereby that if you hit the square peg hard and often enough the round holes will really become square, although you may splinter the board in the process.

The foregoing result is directly contrary to long established tort principles. Once again, in the words of Dean Prosser, the applicable rule is: “[Plaintiff] must introduce evidence which affords a reasonable basis for the conclusion that it is more likely than not that the conduct of the defendant was a substantial factor in bringing about the result. A mere possibility of such causation is not enough, and when the matter remains one of pure speculation or conjecture, or the probabilities are at best evenly balanced, it becomes the duty of the court to direct a verdict for the defendant.” (Prosser, supra, § 41, at p. 241, italics added, fns. *617omitted.) Under the majority’s new reasoning, however, a defendant is fair game if it happens to be engaged in a similar business and causation is possible, even though remote.

In passing, I note the majority’s dubious use of market share data. It is perfectly proper to use such information to assist in proving, circumstantially, that a particular defendant probably caused plaintiffs’ injuries. Circumstantial evidence may be used as a basis for proving the requisite probable causation. (Id., at p. 242.) The majority, however, authorizes the use of such evidence for an entirely different purpose, namely, to impose and allocate liability among multiple defendants only one of whom may have produced the drug which injured plaintiffs. Because this use of market share evidence does not implicate any particular defendant, I believe such data are entirely irrelevant and inadmissible, and that the majority errs in such use. In the absence of some statutory authority there is no legal basis for such use.

Although seeming to acknowledge that imposition of liability upon defendants who probably did not cause plaintiffs’ injuries is unfair, the majority justifies this inequity on the ground that “each manufacturer’s liability for an injury would be approximately equivalent to the damages caused by the DES it manufactured.” (Ante, p. 613.) In other words, because each defendant’s liability is proportionate to its market share, supposedly “each manufacturer’s liability would approximate its responsibility for the injuries caused by his own products.” (Ante, p. 612.) The majority dodges the “practical problems” thereby presented, choosing to describe them as “matters of proof.” However, the difficulties, in my view, are not so easily ducked, for they relate not to evidentiary matters but to the fundamental question of liability itself.

Additionally, it is readily apparent that “market share” liability will fall unevenly and disproportionately upon those manufacturers who are amenable to suit in California. On the assumption that no other state will adopt so radical a departure from traditional tort principles, it may be concluded that under the majority’s reasoning those defendants who are brought to trial in this state will bear effective joint responsibility for 100 percent of plaintiffs’ injuries despite the fact that their “substantial” aggregate market share may be considerably less. This undeniable fact forces the majority to concede that, “a defendant may be held liable for a somewhat different percentage of the damage than its share of the appropriate market would justify.” (Ante, pp. 612-613.) *618With due deference, I suggest that the complete unfairness of such a result in a case involving only five of two hundred manufacturers is readily manifest.

Furthermore, several other important policy considerations persuade me that the majority holding is both inequitable and improper. The injustice inherent in the majority’s new theory of liability is compounded by the fact that plaintiffs who use it are treated far more favorably than are the plaintiffs in routine tort actions. In most tort cases plaintiff knows the identity of the person who has caused his injuries. In such a case, plaintiff, of course, has no option to seek recovery from an entire industry or a “substantial” segment thereof, but in the usual instance can recover, if at all, only from the particular defendant causing injury. Such a defendant may or may not be either solvent or amenable to process. Plaintiff in the ordinary tort case must take a chance that defendant can be reached and can respond financially. On what principle should those plaintiffs who wholly fail to prove any causation, an essential element of the traditional tort cause of action, be rewarded by being offered both a wider selection of potential defendants and a greater opportunity for recovery?

The majority attempts to justify its new liability on the ground that defendants herein are “better able to bear the cost of injury resulting from the manufacture of a defective product.” (Ante, p. 611.) This “deep pocket” theory of liability, fastening liability on defendants presumably because they are rich, has understandable popular appeal and might be tolerable in a case disclosing substantially stronger evidence of causation than herein appears. But as a general proposition, a defendant’s wealth is an unreliable indicator of fault, and should play no part, at least consciously, in the legal analysis of the problem. In the absence of proof that a particular defendant caused or at least probably caused plaintiff’s injuries, a defendant’s ability to bear the cost thereof is no more pertinent to the underlying issue of liability than its “substantial” share of the relevant market. A system priding itself on “equal justice under law” does not flower when the liability as well as the damage aspect of a tort action is determined by a defendant’s wealth. The inevitable consequence of such a result is to create and perpetuate two rules of law—one applicable to wealthy defendants, and another standard pertaining to defendants who are poor or who have modest means. Moreover, considerable doubts have been expressed regarding the ability of the drug industry, and especially its smaller members, to bear the substantial economic costs (from both damage awards and *619high insurance premiums) inherent in imposing an industry-wide liability. (See Coggins, supra, 13 Suffolk L.Rev. at pp. 1003-1006, 1010-1011.)

An important and substantial countervailing public policy in defendants’ favor was very recently expressed in a similar DES case, McCreery v. Eli Lilly & Co., supra, 87 Cal.App.3d 77, 86-87. Although the majority herein impliedly rejects the appellate court’s holding, in my opinion pertinent language of the McCreery court, based upon the Restatement of Torts and bearing on the majority’s “market share” theory, is well worth repeating: “Application of the comments to the Restatement Second of Torts, section 402A, to this situation compels a rejection of the imposition of liability. As the comment states, ‘... It is also true in particular of many new or experimental drugs as to which, because of lack of time and opportunity for sufficient medical experience, there can be no assurance of safety, or perhaps even of purity of ingredients, but such experience as there is justifies the marketing and use of the drug notwithstanding a medically recognizable risk. The seller of such products, again, with the qualification that they are properly prepared and marketed, and proper warning is given, where the situation calls for it, is not to be held to strict liability for unfortunate consequences attending their use, merely because he has undertaken to supply the public with an apparently useful and desirable product, attended with a known but apparently reasonable risk.’ (Rest. 2d Torts, § 402A, com. k.) This section implicitly recognizes the social policy behind the development of new pharmaceutical preparations. As one commentator states, ‘[t]he social and economic benefits from mobilizing the industry’s resources in the war against disease and in reducing the costs of medical care are potentially enormous. The development of new drugs in the last three decades has already resulted in great social benefits. The potential gains from further advances remain large. To risk such gains is unwise. Our major objective should be to encourage a continued high level of industry investment in pharmaceutical R & D [research and development].’ (Schwartzman, The Expected Return from Pharmaceutical Research: Sources of New Drugs and the Profitability of R & D Investment (1975) p. 54.)” (McCreery v. Eli Lilly & Co., supra, 87 Cal.App.3d 77, 86-87, italics added; see also Coggins, supra, 13 Suffolk L.Rev. at p. 1004.)

In the present case the majority imposes liability more than 20 years after ingestion of drugs which at the time they were used, after careful *620testing, had the full approval of the United States Food and Drug Administration. It seems to me that liability in the manner created by the majority must inevitably inhibit, if not the research or development, at least the dissemination of new pharmaceutical drugs. Such a result, as explained by the Restatement, is wholly inconsistent with traditional tort theory.

I also suggest that imposition of so sweeping a liability may well prove to be extremely shortsighted from the standpoint of broad social policy. Who is to say whether, and at what time and in what form, the drug industry upon which the majority now fastens this blanket liability, may develop a miracle drug critical to the diagnosis, treatment, or, indeed, cure of the very disease in question? It is counterproductive to inflict civil damages upon all manufacturers for the side effects and medical complications which surface in the children of the users a generation after ingestion of the drugs, particularly when, at the time of their use, the drugs met every fair test and medical standard then available and applicable. Such a result requires of the pharmaceutical industry a foresight, prescience and anticipation far beyond the most exacting standards of the relevant scientific disciplines. In effect, the majority requires the pharmaceutical research laboratory to install a piece of new equipment—the psychic’s crystal ball.

I am not unmindful of the serious medical consequences of plaintiffs’ injuries, and the equally serious implications to the class which she purports to represent. In balancing the various policy considerations, however, I also observe that the incidence of vaginal cancer among “DES daughters” has been variously estimated at one-tenth of 1 percent to four-tenths of 1 percent. (13 Suffolk L.Rev., supra, p. 999, fn. 92.) These facts raise some penetrating questions. Ninety-nine plus percent of “DES daughters” have never developed cancer. Must a drug manufacturer to escape this blanket liability wait for a generation of testing before it may disseminate drugs similar to DES? If a drug has beneficial purposes for the majority of users but harmful side-effects are later revealed for a small fraction of consumers, will the manufacturer be absolutely liable? If adverse medical consequences, wholly unknown to the most careful and meticulous of present scientists, surface in two or three generations, will similar liability be imposed? In my opinion, common sense and reality combine to warn that a “market share” theory goes too far. Legally, it expects too much.

*621I believe that the scales of justice tip against imposition of this new liability because of the foregoing elements of unfairness to some defendants who may have had nothing whatever to do with causing any injury, the unwarranted preference created for this particular class of plaintiffs, the violence done to traditional tort principles by the drastic expansion of liability proposed, the injury threatened to the public interest in continued unrestricted basic medical research as stressed by the Restatement, and the other reasons heretofore expressed.

The majority’s decision effectively makes the entire drug industry (or at least its California members) an insurer of all injuries attributable to defective drugs of uncertain or unprovable origin, including those injuries manifesting themselves a generation later, and regardless of whether particular defendants had any part whatever in causing the claimed injury. Respectfully, I think this is unreasonable overreaction for the purpose of achieving what is perceived to be a socially satisfying result.

Finally, I am disturbed by the broad and ominous ramifications of the majority’s holding. The law review comment, which is the wellspring of the majority’s new theory, conceding the widespread consequences of industry-wide liability, openly acknowledges that “The DES cases are only the tip of an iceberg.” (Comment, DES and a Proposed Theory of Enterprise Liability (1978) 46 Fordham L.Rev. 963, 1007.) Although the pharmaceutical drug industry may be the first target of this new sanction, the majority’s reasoning has equally threatening application to many other areas of business and commercial activities.

Given the grave and sweeping economic, social, and medical effects of “market share” liability, the policy decision to introduce and define it should rest not with us, but with the Legislature which is currently considering not only major statutory reform of California product liability law in general, but the DES problem in particular. (See Sen. Bill No. 1392 (1979-1980 Reg. Sess.), which would establish and appropriate funds for the education, identification, and screening of persons exposed to DES, and would prohibit health care and hospital service plans from excluding or limiting coverage to persons exposed to DES.) An alternative proposal for administrative compensation, described as “a limited version of no-fault products liability” has been suggested by one commentator. (Coggins, supra, 13 Suffolk L.Rev. at pp. 1019-1021.) Compensation under such a plan would be awarded by an administra*622tive tribunal from funds collected “via a tax paid by all manufacturers.” (P. 1020, fn. omitted.) In any event, the problem invites a legislative rather than an attempted judicial solution.

I would affirm the judgments of dismissal.

Clark, J., and Manuel, J., concurred.

Respondents’ petitions for a rehearing were denied May 7, 1980. Tobriner, J., did not participate therein. White, J.,* participated therein. Clark, J., Richardson, J., and Manuel, J., were of the opinion that the petitions should be granted.

Dore, J.

This appeal raises the issue of whether an estate can maintain an action for professional negligence as a result of failure to timely diagnose lung cancer, where the estate can show probable reduction in statistical chance for survival but cannot show and/or prove that with timely diagnosis and treatment, decedent probably would have lived to normal life expectancy.

Both counsel advised that for the purpose of this appeal we are to assume that the respondent Group Health Cooperative of Puget Sound and its personnel negligently failed to diagnose Herskovits' cancer on his first visit to the hospital and proximately caused a 14 percent reduction in his chances of survival. It is undisputed that Herskovits had *611less than a 50 percent chance of survival at all times herein.

The main issue we will address in this opinion is whether a patient, with less than a 50 percent chance of survival, has a cause of action against the hospital and its employees if they: are negligent in diagnosing a lung cancer which reduces his chances of survival by 14 percent.

The personal representative of Leslie Herskovits' estate initiated this survivorship action against Group Health Cooperative of Puget Sound (Group Health), alleging failure to make an early diagnosis of her husband's lung cancer. Group Health moved for summary judgment for dismissal on the basis that Herskovits probably would have died from lung cancer even if the diagnosis had been made earlier, which the trial court granted.

I

The complaint alleged that Herskovits came to Group Health Hospital in 1974 with complaints of pain and coughing. In early 1974, chest X-rays revealed infiltrate in the left lung. Rales and coughing were present. In mid-1974, there were chest pains and coughing, which became persistent and chronic by fall of 1974. A December 5, 1974, entry in the medical records confirms the cough problem. Plaintiff contends that Herskovits was treated thereafter only with cough medicine. No further effort or inquiry was made by Group Health concerning his symptoms, other than an occasional chest X-ray. In the early spring of 1975, Mr. and Mrs. Herskovits went south in the hope that the warm weather would help. Upon his return to the Seattle area with no improvement in his health, Herskovits visited Dr. Jonathan Ostrow on a private basis for another medical opinion. Within 3 weeks, Dr. Ostrow's evaluation and direction to Group Health led to the diagnosis of cancer. In July of 1975, Herskovits' lung was removed, but no radiation or chemotherapy treatments were instituted. Hersko-vits died 20 months later, on March 22, 1977, at the age of 60.

At hearing on the motion for summary judgment, plain*612tiff was unable to produce expert testimony that the delay in diagnosis "probably" or "more likely than not" caused her husband's death. The affidavit and deposition of plaintiff's expert witness, Dr. Jonathan Ostrow, construed in the most favorable light possible to plaintiff, indicated that had the diagnosis of lung cancer been made in December 1974, the patient's possibility of 5-year survival was 39 percent. At the time of initial diagnosis of cancer 6 months later, the possibility of a 5-year survival was reduced to 25 percent. Dr. Ostrow testified he felt a diagnosis perhaps could have been made as early as December 1974, or January 1975, about 6 months before the surgery to remove Mr. Hersko-vits' lung in June 1975.

Dr. Ostrow testified that if the tumor was a "stage 1" tumor in December 1974, Herskovits' chance of a 5-year survival would have been 39 percent. In June 1975, his chances of survival were 25 percent assuming the tumor had progressed to "stage 2". Thus, the delay in diagnosis may have reduced the chance of a 5-year survival by 14 percent.

Dr. William Spence, one of the physicians from Group Health Hospital who cared for the deceased Herskovits, testified that in his opinion, based upon a reasonable medical probability, earlier diagnosis of the lung cancer that afflicted Herskovits would not have prevented his death, nor would it have lengthened his life. He testified that nothing the doctors at Group Health could have done would have prevented Herskovits' death, as death within several years is a virtual certainty with this type of lung cancer regardless of how early the diagnosis is made.

Plaintiff contends that medical testimony of a reduction of chance of survival from 39 percent to 25 percent is sufficient evidence to allow the proximate cause issue to go to the jury. Defendant Group Health argues conversely that Washington law does not permit such testimony on the issue of medical causation and requires that medical testimony must be at least sufficiently definite to establish that the act complained of "probably" or "more likely than not" *613caused the subsequent disability. It is Group Health's contention that plaintiff must prove that Herskovits "probably" would have survived had the defendant not been allegedly negligent; that is, the plaintiff must prove there was at least a 51 percent chance of survival.

Pursuant to CR 56(c), summary judgment is appropriate only where there is no genuine issue as to any material fact and the moving party is entitled to judgment as a matter of law. All reasonable inferences from the evidence must be resolved against the moving party, and in favor of the non-moving party. Lamon v. McDonnell Douglas Corp., 91 Wn.2d 345, 588 P.2d 1346 (1979).

II

This court has held that a person who negligently renders aid and consequently increases the risk of harm to those he is trying to assist is liable for any physical damages he causes. Brown v. MacPherson's, Inc., 86 Wn.2d 293, 299, 545 P.2d 13 (1975). In Brown, the court cited Restatement (Second) of Torts § 323 (1965), which reads:

One who undertakes ... to render services to another which he should recognize as necessary for the protection of the other's person or things, is subject to liability to the other for physical harm resulting from his failure to exercise reasonable to his if

(a) his failure to exercise such care increases the risk of such harm,. . .

This court heretofore has not faced the issue of whether, under section 323(a), proof that the defendant's conduct increased the risk of death by decreasing the chances of survival is sufficient to take the issue of proximate cause to the jury. Some courts in other jurisdictions have allowed the proximate cause issue to go to the jury on this type of proof. See McBride v. United States, 462 F.2d 72 (9th Cir. 1972); Hamil v. Bashline, 481 Pa. 256, 392 A.2d 1280 (1978); Kallenberg v. Beth Israel Hasp., 45 A.D.2d 177, 357 N.Y.S.2d 508 (1974); Jeanes v. Milner, 428 F.2d 598 (8th Cir. 1970); Hicks v. United States, 368 F.2d 626 (4th Cir. 1966). These courts emphasized the fact that defendants' *614conduct deprived the decedents of a "significant" chance to survive or recover, rather than requiring proof that with absolute certainty the defendants' conduct caused the physical injury. The underlying reason is that it is not for the wrongdoer, who put the possibility of recovery beyond realization, to say afterward that the result was inevitable. See also Wolfstone & Wolfstone, Recovery of Damages for the Loss of a Chance, Pers. Inj. Ann. 744 (1978).

Other jurisdictions have rejected this approach, generally holding that unless the plaintiff is able to show that it was more likely than not that the harm was caused by the defendant's negligence, proof of a decreased chance of survival is not enough to take the proximate cause question to the jury. Cooper v. Sisters of Charity, Inc., 27 Ohio St. 2d 242, 272 N.E.2d 97 (1971); Hiser v. Randolph, 126 Ariz. 608, 617 P.2d 774 (Ct. App. 1980); Hanselmann v. McCar-dle, 275 S.C. 46, 267 S.E.2d 531 (1980); Cornfeldt v. Tongen, 295 N.W.2d 638 (Minn. 1980). These courts have concluded that the defendant should not be liable where the decedent more than likely would have died anyway.

The ultimate question raised here is whether the relationship between the increased risk of harm and Herskovits' death is sufficient to hold Group Health responsible. Is a 36 percent (from 39 percent to 25 percent) reduction in the decedent's chance for survival sufficient evidence of causation to allow the jury to consider the possibility that the physician's failure to timely diagnose the illness was the proximate cause of his death? We answer in the affirmative. To decide otherwise would be a blanket release from liability for doctors and hospitals any time there was less than a 50 percent chance of survival, regardless of how flagrant the negligence.

Ill

We are persuaded by the reasoning of the Pennsylvania Supreme Court in Hamil v. Bashline, supra. While Hamil involved an original survival chance of greater than 50 percent, we find the rationale used by the Hamil court to *615apply equally to cases such as the present one, where the original survival chance is less than 50 percent. The plaintiff's decedent was suffering from severe chest pains. His wife transported him to the hospital where he was negligently treated in the emergency unit. The wife, because of the lack of help, took her husband to a private physician's office, where he died. In an action brought under the wrongful death and survivorship statutes, the main medical witness testified that if the hospital had employed proper treatment, the decedent would have had a substantial chance of surviving the attack. The medical expert expressed his opinion in terms of a 75 percent chance of survival. It was also the doctor's opinion that the substantial loss of a chance of recovery was the result of the defendant hospital's failure to provide prompt treatment. The defendant's expert witness testified that the patient would have died regardless of any treatment provided by the defendant hospital.

The Hamil court reiterated the oft-repeated principle of tort law that the mere occurrence of an injury does not prove negligence, but the defendant's conduct must be a proximate cause of the plaintiff's injury. The court also referred to the traditional "but for" test, with the qualification that multiple causes may culminate in injury. Hamil, at 266.

The court then cited Restatement (Second) of Torts § 323 (1965) as authority to relax the degree of certitude normally required of plaintiff's evidence in order to make a case for the jury. The court held that once a plaintiff has introduced evidence that a defendant's negligent act or omission increased the risk of harm to a person in plaintiff's position, and that the harm was in fact sustained, "it becomes a question for the jury as to whether or not that increased risk was a substantial factor in producing the harm". Hamil, at 269. See also C. McCormick, Damages § 31 (1935); Wolfstone & Wolfstone, supra at 744.

The Hamil court distinguished the facts of that case from the general tort case in which a plaintiff alleges that a *616defendant's act or omission set in motion a force which resulted in harm. In the typical tort case, the "but for" test, requiring proof that damages or death probably would not have occurred "but for" the negligent conduct of the defendant, is appropriate. In Hamil and the instant case, however, the defendant's act or omission failed in a duty to protect against harm from another source. Thus, as the Hamil court noted, the fact finder is put in the position of having to consider not only what did occur, but also what might have occurred. Hamil states at page 271:

Such cases by their very nature elude the degree of certainty one would prefer and upon which the law normally insists before a person may be held liable. Nevertheless, in order that an actor is not completely insulated because of uncertainties as to the consequences of his negligent conduct, Section 323(a) tacitly acknowledges this difficulty and permits the issue to go to the jury upon a less than normal threshold of proof.

(Footnote omitted.) The Hamil court held that once a plaintiff has demonstrated that the defendant's acts or omissions have increased the risk of harm to another, such evidence furnishes a basis for the jury to make a determination as to whether such increased risk was in turn a substantial factor in bringing about the resultant harm.

In Hicks v. United States, supra, the Court of Appeals set forth the rationale for deviation from the normal requirements of proof in a case such as the one presently before us. The following quotation from Hicks, at 632, is frequently cited in cases adopting loss of a chance because it succinctly defines the doctrine:

Rarely is it possible to demonstrate to an absolute certainty what would have happened in circumstances that the wrongdoer did not allow to come to pass. The law does not in the existing circumstances require the plaintiff to show to a certainty that the patient would have lived had she been hospitalized and operated on promptly.

Under the Hamil decision, once a plaintiff has demonstrated that defendant's acts or omissions in a situation to *617which section 323(a) applies have increased the risk of harm to another, such evidence furnishes a basis for the fact finder to go further and find that such increased risk was in turn a substantial factor in bringing about the resultant harm. The necessary proximate cause will be established if the jury finds such cause. It is not necessary for a plaintiff to introduce evidence to establish that the negligence resulted in the injury or death, but simply that the negligence increased the risk of injury or death. The step from the increased risk to causation is one for the jury to make. Hamil, at 272.

In Jeanes v. Milner, supra, the plaintiff mother brought a malpractice action for the death of her child from throat cancer, claiming delayed diagnosis of 1 month caused a shortened life span and pain and suffering. The United States Court of Appeals for the Eighth Circuit, reversing a dismissal for insufficient evidence on the element of proximate cause, held at pages 604-05:

We cannot agree with the District Court's holding that "there is no evidence from which the jury could find that the delay of approximately one month in the transmission of [the] slides could have been the proximate cause of [Tommy's] failure to recover from his cancer, or to increase his pain and suffering or to shorten his life." Nor can we agree that the jury could "only find a verdict for the plaintiff based on speculation and conjecture."

The Supreme Court of the United States has spoken to a contention similar to that argued here by the doctors and the Infirmary. In Lavender v. Kurn, 327 U.S. 645, 653, 66 S.Ct. 740, 90 L.Ed. 916 (1946), the Court stated:

"It is no answer to say that the jury's verdict speculation and conjecture. Whenever facts are in dispute or the evidence is such that fair-minded men may draw different inferences, a measure of speculation and conjecture is required on the part of those whose duty it is to settle the dispute by choosing what seems them to be the most reasonable inference."

The recent case of James v. United States, 483 F. Supp. 581 (N.D. Cal. 1980) concerned the failure to diagnose and *618promptly treat a lung tumor. The court concluded that the plaintiff sustained its burden of proof even without statistical evidence, stating at page 587:

As a proximate result of defendant's negligence, James was deprived of the opportunity to receive early treatment and the chance of realizing any resulting gain in his life expectancy and physical and mental comfort. No matter how small that chance may have been — and its magnitude cannot be ascertained — no one can say that the chance of prolonging one's life or decreasing suffering is valueless.

(Italics ours.)

Where percentage probabilities and decreased probabilities are submitted into evidence, there is simply no danger of speculation on the part of the jury. More speculation is involved in requiring the medical expert to testify as to what would have happened had the defendant not been negligent. McCormick, supra.

Chester v. United States, 403 F. Supp. 458, 460 (W.D. Pa. 1975) was a medical malpractice suit for negligent failure to diagnose and treat cancer of the esophagus. The court found that in November 1972, the decedent was exhibiting symptoms and complaints that were consistent with cancer. No tests were performed to determine what was causing the illness, and the court determined this was below the accepted medical standard of care. Further, the judge decided that the cancer was indeed present in November 1972, and could have been treated or resected before metastasis. The judge reasoned that, if there was a possibility that the decedent had carcinoma of the esophagus, the hospital doctors were negligent in treating him for hypertension only.

The Chester court then awarded damages of $45,988.10, including $36,741.10 for loss of earning power, $7,500 for the loss of guidance, etc., for his minor children, and $1,747 for funeral expenses. This damage award is consistent with our reasoning in Wooldridge v. Woolett, 96 Wn.2d 659, 638 P.2d 566 (1981) where we held that a decedent's shortened *619life expectancy is not recoverable as a separate item of damages, but will be considered as it affects the loss of value of his future earning capacity.

Conclusion

Both counsel have agreed for the purpose of arguing this summary judgment that the defendants were negligent in failing to make a diagnosis of cancer on Herskovits' initial visit in December 1974, and that such negligence was the proximate cause of reducing his chances of survival by 14 percent. It is undisputed that Herskovits had less than a 50 percent chance of survival at that time. Based on this agreement and Dr. Ostrow's deposition and affidavit, a prima facie case is shown. We reject Group Health's argument that plaintiffs must show that Herskovits "probably" would have had a 51 percent chance of survival if the hospital had not been negligent. We hold that medical testimony of a reduction of chance of survival from 39 percent to 25 percent is sufficient evidence to allow the proximate cause issue to go to the jury.

Causing reduction of the opportunity to recover (loss of chance) by one's negligence, however, does not necessitate a total recovery against the negligent party for all damages caused by the victim's death. Damages should be awarded to the injured party or his family based only on damages caused directly by premature death, such as lost earnings and additional medical expenses, etc.

We reverse the trial court and reinstate the cause of action.

Rosellini, J., concurs.

Pearson, J.

(concurring) — I agree with the majority that the trial court erred in granting defendant's motion for summary judgment. I cannot, however, agree with the majority's reasoning in reaching this decision. The majority's reliance on Hamil v. Bashline, 481 Pa. 256, 392 A.2d 1280 (1978) and Hicks v. United States, 368 F.2d 626 (4th Cir. 1966) is inappropriate for the reasons identified in the *620dissent of Justice Dolliver. Moreover, the issue before us is considerably more complex than the apparently straightforward policy choice suggested by the interaction of the majority opinion and Justice Dolliver's dissent. I therefore agree with Justice Brachtenbach that those opinions fail to focus on the key issue. I decline to join Justice Brachten-bach’s dissent, however, because the result he advocates is harsh, as he recognizes at page 642. In an effort to achieve a fair result by means of sound analysis, I offer the following approach.

This action began in July 1979 with a complaint alleging that defendant Group Health Cooperative had negligently treated the decedent Leslie Herskovits. Plaintiff, the widow of decedent Herskovits, alleged in this complaint that defendant's failure to diagnose the decedent's lung cancer "led to and caused his death". The complaint sought damages for the medical expenses, disability, and pain and suffering of the decedent, together with pecuniary loss suffered by plaintiff, including loss of support, affection, and consortium.

As discovery progressed, some undisputed facts were established. Mr. Herskovits had been a patient of the Group Health Cooperative for more than 20 years. In December 1974, he consulted a physician at Group Health for the treatment of a persistent cough. The physician prescribed cough medicine. Obtaining no relief from his cough, Mr. Herskovits consulted a physician outside Group Health, Dr. Jonathan Ostrow. Dr. Ostrow suspected that Mr. Herskovits had lung cancer, and recommended a medical procedure be undertaken to confirm his suspicions. The procedure was performed in June 1975, and revealed that Mr. Herskovits had cancer in the bronchus of his left lung. The lung was removed on July 1, 1975. Mr. Herskovits died of cancer on March 22, 1977, at the age of 60 years.

Defendant moved for summary judgment in May 1981, on the ground that plaintiff was unable to produce testimony that earlier diagnosis would probably have prevented Mr. Herskovits' death from cancer. The trial court granted *621the motion and dismissed the action, holding that plaintiff had "failed to produce expert testimony which would establish that the decedent probably would not have died on or about March, 1977 but for the conduct of the defendant". This holding was based on the court's conclusion that "under Washington law the loss of a possibility of survival is not compensable".

Plaintiff's case was based on the testimony of the expert witness, Dr. Ostrow. This court's enquiry, therefore, is whether Dr. Ostrow's testimony, together with reasonable inferences therefrom, creates a prima facie issue of causation. Lamon v. McDonnell Douglas Corp., 91 Wn.2d 345, 588 P.2d 1346 (1979). The critical testimony of Dr. Ostrow, from his affidavit and deposition, may fairly be summarized as follows:

1. There is a reasonable medical probability that defendant failed to take necessary steps to diagnose Mr. Hersko-vits' condition, and defendant therefore failed to meet the appropriate standard of care.

2. Had reasonable care been exercised, Mr. Herskovits' cancer could have been diagnosed in December 1974 instead of June 1975.

3. Unless removed, a cancerous tumor can be expected to increase in size over time, and the patient's chances of survival decline accordingly.

4. There is no way of knowing how far the tumor in Mr. Herskovits' lung had developed by December 1974.

5. If the tumor had been a stage 1 tumor in December 1974, decedent's statistical chance of surviving 5 years was 39 percent.

6. When the tumor was discovered in June 1975, it was a stage 2 tumor. The statistical chance of surviving 5 years when the tumor has reached stage 2 is 25 percent.

7. Dr. Ostrow summed up his opinion as follows: "By failing to properly evaluate Mr. Herskovits' condition as late as December 1974, Group Health probably caused Mr. Herskovits' chance for long-term survival to be substantially reduced".

*622Dr. Ostrow's testimony does not, therefore, establish a prima facie case that defendant's alleged negligence probably (or more likely than not) caused Mr. Herskovits' death. Rather, the testimony establishes only that the alleged negligence caused a substantial reduction in Mr. Hersko-vits' long-term chance of survival. Dr. Ostrow testified that if the tumor was at stage 1 in December 1974, the chance of survival was reduced from 39 percent to 25 percent. He did not, however, indicate the likelihood of the tumor's being at stage 1 in December 1974, either in terms of certainty, probability, or statistical chance. Therefore, the only indications from the record of the extent of the reduction in Mr. Herskovits' chance of long-term survival are that it was "substantial" and that it was at most a 14 percent reduction (from 39 percent to 25 percent).

I turn now to consider whether this testimony is sufficient to create a material issue whether defendant's alleged negligence was a proximate cause of harm to plaintiff. Recently, we stated that

[pjroximate cause must be established by, first, a showing that the breach of duty was a cause in fact of the injury, and, second, a showing that as a matter of law liability should attach. . . . Cause in fact can be established by proving that but for the breach of duty, the injury would not have occurred.

Harbeson v. Parke-Davis, Inc., 98 Wn.2d 460, 476, 656 P.2d 483 (1983). In the present case, we must determine whether cause in fact has been established.

In medical malpractice cases such as the one before us, cause in fact must usually be established by expert medical testimony, and must be established beyond the balance of probabilities.

In a case such as this, medical testimony must be relied upon to establish the causal relationship between the liability-producing situation and the claimed physical disability resulting therefrom. The evidence will be deemed insufficient to support the jury's verdict, if it can be said that considering the whole of the medical testimony the jury must resort to speculation or conjecture in *623determining such causal relationship. In many recent decisions of this court we have held that such determination is deemed based on speculation and conjecture if the medical testimony does not go beyond the expression of an opinion that the physical disability "might have" or "possibly did" result from the hypothesized cause. To remove the issue from the realm of speculation, the medical testimony must at least be sufficiently definite to establish that the act complained of "probably" or "more likely than not" caused the subsequent disability.

O'Donoghue v. Riggs, 73 Wn.2d 814, 824, 440 P.2d 823 (1968).

The issue before the court, quite simply, is whether Dr. Ostrow's testimony satisfies the standard enunciated in O'Donoghue. We must decide whether Dr. Ostrow's testimony established that the act complained of (the alleged delay in diagnosis) "probably" or "more likely than not" caused Mr. Herskovits' subsequent disability. In order to make this determination, we must first define the "subsequent disability" suffered by Mr. Herskovits. Therein lies the crux of this case, for it is possible to define the injury or "disability" to Mr. Herskovits in at least two different ways. First, and most obviously, the injury to Mr. Hersko-vits might be viewed as his death. Alternatively, however, the injury or disability may be seen as the reduction of Mr. Herskovits' chance of surviving the cancer from which he suffered.

Therefore, although the issue before us is primarily one of causation, resolution of that issue requires us to identify the nature of the injury to the decedent. Our conception of the injury will substantially affect our analysis. If the injury is determined to be the death of Mr. Herskovits, then under the established principles of proximate cause plaintiff has failed to make a prima facie case. Dr. Ostrow was unable to state that probably, or more likely than not, Mr. Herskovits' death was caused by defendant's negligence. On the contrary, it is clear from Dr. Ostrow's testimony that Mr. Herskovits would have probably died from cancer even with the exercise of reasonable care by defendant. Accord*624ingly, if we perceive the death of Mr. Herskovits as the injury in this case, we must affirm the trial court, unless we determine that it is proper to depart substantially from the traditional requirements of establishing proximate cause in this type of case.

If, on the other hand, we view the injury to be the reduction of Mr. Herskovits' chance of survival, our analysis might well be different. Dr. Ostrow testified that the failure to diagnose cancer in December 1974 probably caused a substantial reduction in Mr. Herskovits' chance of survival. The O'Donoghue v. Riggs standard of proof is therefore met.

I note here that two other problems are created by the latter analysis. First, we have never before considered whether the loss or reduction of a chance of survival is a compensable injury. And second, this analysis raises the issue of whether an action for reduction of the chance of survival can be brought under the wrongful death statute, RCW 4.20.010.

Confronted with these problems, and with the first impression choice between the two approaches to the issue before us, I turn to consider how other jurisdictions have dealt with similar cases.

One approach, and that urged by defendant, is to deny recovery in wrongful death cases unless the plaintiff establishes that decedent would probably have survived but for defendant's negligence. This approach is typified by Cooper v. Sisters of Charity, Inc., 27 Ohio St. 2d 242, 272 N.E.2d 97 (1971). The court in that case affirmed a directed verdict for defendant where the only evidence of causation was that decedent had a chance "maybe some place around 50%" of survival had defendant not been negligent. The court said in 27 Ohio St. 2d at 253-54:

In an action for wrongful death, where medical malpractice is alleged as the proximate cause of death, and plaintiff's evidence indicates that a failure to diagnose the injury prevented the patient from an opportunity to be operated on, which failure eliminated any chance of *625the patient's survival, the issue of proximate cause can be submitted to a jury only if there is sufficient evidence showing that with proper diagnosis, treatment and surgery the patient probably would have survived.

This case was followed in Hiser v. Randolph, 126 Ariz. 608, 617 P.2d 774 (Ct. App. 1980). The Arizona court explicitly rejected both Hamil u. Bashline and Hicks v. United States (the leading cases cited by plaintiffs in the case before us) and agreed with Cooper that "the mere loss of an unspecified increment of the chance for survival is, of itself, insufficient to meet the standard of probability". 126 Ariz. at 613.

On the other hand, plaintiff cites seven cases in support of her position. Hicks v. United States, 368 F.2d 626 (4th Cir. 1966); Jeanes v. Milner, 428 F.2d 598 (8th Cir. 1970); O'Brien v. Stover, 443 F.2d 1013 (8th Cir. 1971); McBride v. United States, 462 F.2d 72 (9th Cir. 1972); Kallenberg v. Beth Israel Hosp., 45 A.D.2d 177, 357 N.Y.S.2d 508, aff'd, 37 N.Y.2d 719, 337 N.E.2d 128, 374 N.Y.S.2d 615 (1974); Hamil v. Bashline, 481 Pa. 256, 392 A.2d 1280 (1978); James v. United States, 483 F. Supp. 581 (N.D. Cal. 1980). The complexity of the issue and elusive nature of the rationales of these opinions persuade me to discuss them at some length.

The first case, Hicks, was an action under the Federal Tort Claims Act, to recover damages for the death of a 25-year-old woman from an undiagnosed bowel obstruction. The uncontradicted testimony of the plaintiff's experts was that "if operated on promptly, [the patient] would have survived". 368 F.2d at 632.

The District Court, construing the laws of Virginia, concluded that there was insufficient evidence that the conced-edly erroneous diagnosis was a proximate cause of the woman's death. The defendant urged the Court of Appeals to affirm the District Court, arguing that even had surgery been performed immediately, it was mere speculation to say that it would have been successful. The Court of Appeals rejected the argument and in what has become an *626oft-quoted passage said:

When a defendant's negligent action or inaction has effectively terminated a person's chance of survival, it does not lie in the defendant's mouth to raise conjectures as to the measure of the chances that he has put beyond the possibility of realization. If there was any substantial possibility of survival and the defendant has destroyed it, he is answerable. Rarely is it possible to demonstrate to an absolute certainty what would have happened in circumstances that the wrongdoer did not allow to come to pass. The law does not in the existing circumstances require the plaintiff to show to a certainty that the patient would have lived had she been hospitalized and operated on promptly. Harvey v. Silber, 300 Mich. 510, 2 N.W.2d 483 (1942).

368 F.2d at 632. The court in Hicks also drew an analogy to another federal case which imposed liability on a ship's master for failing to attempt to rescue a seaman who had fallen overboard. Gardner v. National Bulk Carriers, Inc., 310 F.2d 284, 91 A.L.R.2d 1023 (4th Cir. 1962). The court in Gardner rejected the argument that any breach of duty by the ship's master was not a cause of the seaman's death. It held that once the evidence sustained the reasonable possibility of rescue, total disregard of the duty imposed liability.

The court in Hicks v. United States concluded its opinion with the observation that the defendant's "negligence nullified whatever chance of recovery [the patient] might have had and was the proximate cause of the death”. 368 F.2d at 633.

Hicks is susceptible to two interpretations. On one hand, the court's use of phrases like "substantial possibility of survival" (368 F.2d at 632) and "whatever chance of recovery" (368 F.2d at 633) suggests that a less than 50 percent chance of survival would create a prima facie case of proximate cause. The analogy to the duty of a ship's master reinforces the suggestion that only a "reasonable possibility" of survival need be established. Gardner v. National Bulk Carriers, Inc., 310 F.2d at 287.

*627On the other hand, however, the court had no need to decide such a broad question. There was uncontroverted testimony before the court that the decedent would have survived if operated upon promptly. At the very least, this testimony would establish a probability of survival. All the court had to decide, therefore, was that causation was established by a showing that an operation probably (rather than certainly) would have saved the patient's life. Two passages in the opinion seem to confirm that this is the rationale of the case. First, the court, in the passage quoted above, said that " [t]he law does not. . . require the plaintiff to show to a certainty that the patient would have lived". 368 F.2d at 632. Second, the court, in explaining the similarity between Harvey v. Silber, 300 Mich. 510, 2 N.W.2d 483 (1942) and the facts before it, points out that in Harvey there was testimony to the effect that an operation would probably have saved the decedent's life, and this was sufficient to establish proximate cause. 368 F.2d at 632 n.2.

Hicks v. United States, therefore, appears to be authority for no more than the proposition that proximate cause may be established on a probability of survival. This, of course, is entirely consistent with the existing principles of this state under O'Donoghue v. Riggs, and provides little direct support for plaintiff in the present case.

Subsequent cases, however, have relied on the expansive dicta in Hicks to allow recovery for the reduction of a less than probable chance of survival. The first such case was Jeanes v. Milner, 428 F.2d 598 (8th Cir. 1970). This was a malpractice action brought by the mother of a 13-year-old boy who died of throat cancer. The plaintiff alleged that the defendant's negligence had delayed diagnosis of the cancer for over a month. The plaintiff presented expert testimony that during that month the decedent's cancer had progressed from stage 1 to stage 2. Testimony also indicated that patients whose cancer is diagnosed at stage 1 have a statistical survival rate of 35 percent; patients at stage 2 have a survival rate of 24 percent.

*628The Court of Appeals, reversing the District Court, held that this was sufficient evidence from which to infer that the patient's "life would have been saved or at least prolonged and his pain lessened had he received early treatment." 428 F.2d at 604. This conclusion was supported by reference to Hicks, which was described as "persuasive". 428 F.2d at 605.

Both Jeanes and Hicks were cited in another case from the Eighth Circuit in which the plaintiff alleged a negligent delay in the diagnosis of cancer. O'Brien v. Stover, 443 F.2d 1013 (8th Cir. 1971). Causation was apparently established in O'Brien by testimony that "there is an overall 30 per cent survival rate from this type of cancer and that chance is considerably improved the earlier the cancer is discovered". 443 F.2d at 1018. Among the elements of damages which the court approved was reduction of the patient's "chances for survival, or at least living longer and more comfortably". 443 F.2d at 1019.

The fourth case cited by plaintiff, McBride v. United States, is based upon the proposition that

When a plaintiff's cause of action rests upon an allegedly negligent failure to give necessary treatment, he must show, with reasonable medical probability, that the treatment would have successfully prevented the patient's injury.

462 F.2d at 75. This is the rationale also of Cooper v. Sisters of Charity, Inc., 27 Ohio St. 2d 242, 272 N.E.2d 97 (1971), and clearly of no assistance to plaintiff in the case before us.

The fifth case, Kallenberg v. Beth Israel Hosp., is a more extreme approach. The Appellate Division of the New York Supreme Court upheld a jury verdict of $55,000 in a wrongful death action. The jury had heard testimony from the plaintiff's witness that defendant's negligence was a "producing, contributing factor" in the death and further that "’if properly treated . . . the patient still [would have had] a 20, say 30, maybe 40% chance of survival'". 45 A.D.2d at 179. The appellate court noted that proximate *629cause is a jury question and concluded, without citing authority, that the testimony reviewed was sufficient for the jury to find that, but for the defendant's negligence, the decedent might have made a recovery.

Plaintiff relies most heavily on the next case, Hamil v. Bashline. This was a wrongful death action based upon the alleged negligence of the defendant hospital's failure to treat the decedent, who subsequently died of a heart attack. An expert witness for the plaintiff testified that had the decedent received reasonable treatment he would have had a 75 percent chance of surviving the heart attack he was experiencing when admitted to the hospital. The defendant argued that the plaintiff had failed to establish a prima facie case because no testimony was introduced to show that the defendant's negligence did, to a reasonable degree of medical certainty, cause decedent's death.

The Supreme Court of Pennsylvania acknowledged that the general principles of tort law in that state required that expert testimony "establish that the injury in question did, with a reasonable degree of medical certainty, stem from the negligent act alleged”. 481 Pa. at 267. The court recognized an exception to this heavy burden of proof in situations governed by Restatement (Second) of Torts § 323(a) (1965). The court said in 481 Pa. at 269-70:

Section 323(a) recognizes that a particular class of tort actions, of which the case at bar is an example, differs from those cases normally sounding in tort. Whereas typically a plaintiff alleges that a defendant's act or omission set in motion a force which resulted in harm, the theory of the present case is that the defendant's act or omission failed in a duty to protect against harm from another source. To resolve such a claim a fact-finder must consider not only what did occur, but also what might have occurred, i. e., whether the harm would have resulted from the independent source even if defendant had performed his service in a non-negligent manner. Such a determination as to what might have happened necessarily requires a weighing of probabilities.

(Footnote omitted.) The court then quoted the ubiquitous *630passage from Hicks v. United States and observed:

We agree with this statement of the law and hold that once a plaintiff has demonstrated that defendant's acts or omissions, in a situation to which Section 323(a) applies, have increased the risk of harm to another, such evidence furnishes a basis for the fact-finder to go further and find that such increased risk was in turn a substantial factor in bringing about the resultant harm; the necessary proximate cause will have been made out if the jury sees fit to find cause in fact.

(Footnote omitted.) 481 Pa. at 272. In a footnote the court elaborated upon the manner in which the plaintiff must demonstrate that the defendant's acts or omissions increased the risk of harm to the plaintiff. In this footnote, the court quotes from comment a to Restatement (Second) of Torts § 433B(1), to the effect that the plaintiff must establish by a preponderance of the evidence that the conduct of the defendant was a substantial factor in bringing about the harm to the plaintiff. The court continues:

In the instant case, Dr. Wecht testified to a 75% chance of recovery had prompt treatment been administered to Mr. Hamil by Bashline; this was sufficient basis upon which the jury could have concluded that it was more likely than not that the defendant's omissions were a substantial factor in causing Mr. Hamil's death. Of course, as was done here, a defendant may present expert testimony to the opposite effect, i. e., the unlikelihood of survival even had the defendant exercised due care; as always, resolution of conflicting testimony is for the jury.

481 Pa. at 272 n.9.

It is clear that Hamil, like Hicks and McBride, stands for no more than a rejection of a reasonable certainty standard of proof, and an acceptance of a reasonable probability standard. Viewed thus, it advances plaintiff's case very little.

The final case cited by plaintiff is James v. United States, 483 F. Supp. 581 (N.D. Cal. 1980). In that case, the District Court held that plaintiff's failure to establish a statistically measurable chance of survival did not rule out recovery. The court said, without citing authority:

*631As a proximate result of defendant's negligence, [the decedent] was deprived of the opportunity to receive early treatment and the chance of realizing any resulting gain in his life expectancy and physical and mental comfort. No matter how small that chance may have been— and its magnitude cannot be ascertained — no one can say that the chance of prolonging one's life or decreasing suffering is valueless.

483 F. Supp. at 587.

This decision goes well beyond any of the other cases, allowing recovery for the loss of any chance, no matter how small.

Having concluded this somewhat detailed survey of the cases cited by plaintiff, what conclusions can we draw? First, the critical element in each of the cases is that the defendant's negligence either deprived a decedent of a chance of surviving a potentially fatal condition or reduced that chance. To summarize, in Hicks v. United States the decedent was deprived of a probability of survival; in Jeanes v. Milner the decedent's chance of survival was reduced from 35 percent to 24 percent; in O'Brien v. Stover, the decedent's 30 percent chance of survival was reduced by an indeterminate amount; in McBride v. United States the decedent was deprived of the probability of survival; in Kallenberg v. Beth Israel Hosp. the decedent was deprived of a 20 percent to 40 percent chance of survival; in Hamil v. Bashline the decedent was deprived of a 75 percent chance of survival; and in James v. United States the decedent was deprived of an indeterminate chance of survival, no matter how small.

The three cases where the chance of survival was greater than 50 percent (Hicks, McBride, and Hamil) are unexceptional in that they focus on the death of the decedent as the injury, and they require proximate cause to be shown beyond the balance of probabilities. Such a result is consistent with existing principles in this state, and with cases from other jurisdictions cited by defendant.

The remaining four cases allowed recovery despite the plaintiffs' failure to prove a probability of survival. Three of *632these cases (Jeanes, O'Brien, and James) differ significantly from the Hicks, McBride, and Hamil group in that they view the reduction in or loss of the chance of survival, rather than the death itself, as the injury. Under these cases, the defendant is liable, not for all damages arising from the death, but only for damages to the extent of the diminished or lost chance of survival. The fourth of these cases, Kallenberg, differs from the other three in that it focuses on the death as the compensable injury. This is clearly a distortion of traditional principles of proximate causation. In effect, Kallenberg held that a 40 percent possibility of causation (rather than the 51 percent required by a probability standard) was sufficient to establish liability for the death. Under this loosened standard of proof of causation, the defendant would be liable for all damages resulting from the death for which he was at most 40 percent responsible.

My review of these cases persuades me that the preferable approach to the problem before us is that taken (at least implicitly) in Jeanes, O'Brien, and James. I acknowledge that the principal predicate for these cases is the passage of obiter dictum in Hicks, a case which more directly supports the defendant's position. I am nevertheless convinced that these cases reflect a trend to the most rational, least arbitrary, rule by which to regulate cases of this kind. I am persuaded to this conclusion not so much by the reasoning of these cases themselves, but by the thoughtful discussion of a recent commentator. King, Causation, Valuation, and Chance in Personal Injury Torts Involving Preexisting Conditions and Future Consequences, 90 Yale L.J. 1353 (1981).

King's basic thesis is explained in the following passage, which is particularly pertinent to the case before us.

Causation has for the most part been treated as an all- or-nothing proposition. Either a loss was caused by the defendant or it was not. ... A plaintiff ordinarily should be required to prove by the applicable standard of proof that the defendant caused the loss in question. *633 What caused a loss, however, should be a separate question from what the nature and extent of the loss are. This distinction seems to have eluded the courts, with the result that lost chances in many respects are compensated either as certainties or not at all.

To illustrate, consider the case in which a doctor negligently fails to diagnose a patient's cancerous condition until it has become inoperable. Assume further that even with a timely diagnosis the patient would have had only a 30% chance of recovering from the disease and surviving over the long term. There are two ways of handling such a case. Under the traditional approach, this loss of a not-better-than-even chance of recovering from the cancer would not be compensable because it did not appear more likely [than] not that the patient would have survived with proper care. Recoverable damages, if any, would depend on the extent to which it appeared that cancer killed the patient sooner than it would have with timely diagnosis and treatment, and on the extent to which the delay in diagnosis aggravated the patient's condition, such as by causing additional pain. A more rational approach, however, would allow recovery for the loss of the chance of cure even though the chance was not better than even. The probability of long-term survival would be reflected in the amount of damages awarded for the loss of the chance. While the plaintiff here could not prove by a preponderance of the evidence that he was denied a cure by the defendant's negligence, he could show by a preponderance that he was deprived of a 30% chance of a cure.

90 Yale L.J. at 1363-64.

Under the all or nothing approach, typified by Cooper v. Sisters of Charity, Inc., 27 Ohio St. 2d 242, 272 N.E.2d 97 (1971), a plaintiff who establishes that but for the defendant's negligence the decedent had a 51 percent chance of survival may maintain an action for that death. The defendant will be liable for all damages arising from the death, even though there was a 49 percent chance it would have occurred despite his negligence. On the other hand, a plaintiff who establishes that but for the defendant's negligence the decedent had a 49 percent chance of survival recovers nothing.

*634This all or nothing approach to recovery is criticized by King on several grounds, 90 Yale L.J. at 1376-78. First, the all or nothing approach is arbitrary. Second, it

subverts the deterrence objectives of tort law by denying recovery for the effects of conduct that causes statistically demonstrable losses. ... A failure to allocate the cost of these losses to their tortious sources . . . strikes at the integrity of the torts system of loss allocation.

90 Yale L.J. at 1377. Third, the all or nothing approach creates pressure to manipulate and distort other rules affecting causation and damages in an attempt to mitigate perceived injustices. (Kallenberg v. Beth Israel Hosp. appears to be a good illustration of this tendency.) Fourth, the all or nothing approach gives certain defendants the benefit of an uncertainty which, were it not for their tor-tious conduct, would not exist. (This is reminiscent of the reasoning in the fertile dictum in Hicks v. United States.) Finally, King argues that the loss of a less than even chance is a loss worthy of redress.

These reasons persuade me that the best resolution of the issue before us is to recognize the loss of a less than even chance as an actionable injury. Therefore, I would hold that plaintiff has established a prima facie issue of proximate cause by producing testimony that defendant probably caused a substantial reduction in Mr. Herskovits' chance of survival.

The decedent's personal action for loss of this chance will survive to his personal representatives as provided by RCW 4.20.046. The family of the decedent should also be allowed to maintain an action for the lost chance of recovery by the decedent. I would interpret the wrongful death statute, RCW 4.20.010, to apply to cases of this type. Under this interpretation, a person will "cause" the death of another person (within the meaning of RCW 4.20.010) whenever he causes a substantial reduction in that person's chance of *635survival.1

Finally, it is necessary to consider the amount of damages recoverable in the event that a loss of a chance of recovery is established. Once again, King's discussion provides a useful illustration of the principles which should be applied.

To illustrate, consider a patient who suffers a heart attack and dies as a result. Assume that the defendant-physician negligently misdiagnosed the patient's condition, but that the patient would have had only a 40% chance of survival even with a timely diagnosis and proper care. Regardless of whether it could be said that the defendant caused the decedent's death, he caused the loss of a chance, and that chance-interest should be completely redressed in its own right. Under the proposed rule, the plaintiff's compensation for the loss of the victim's chance of surviving the heart attack would be 40% of the compensable value of the victim's life had he survived (including what his earning capacity would otherwise have been in the years following death). The value placed on the patient's life would reflect such factors as his age, health, and earning potential, including the fact that he had suffered the heart attack and the assumption that he had survived it. The 40% computation would be applied to that base figure.

(Footnote omitted.) 90 Yale L.J. at 1382.2

*636I would remand to the trial court for proceedings consistent with this opinion.

Williams, C.J., and Stafford and Utter, JJ., concur with Pearson, J.

Brachtenbach, J.

(dissenting) — I dissent because I find plaintiff did not meet her burden of proving proximate cause. While the statistical evidence introduced by the expert was relevant and admissible, it was not alone sufficient to maintain a cause of action.

Neither the majority nor Justice Dolliver's dissent focus on the key issue. Both opinions focus on the significance of the 14 percent differentiation in the patient's chance to survive for 5 years and question whether this statistical data is sufficient to sustain a malpractice action. The issue is not so limited. The question should be framed as whether all the evidence amounts to sufficient proof, rising above speculation, that the doctor's conduct was a proximate cause of the patient's death. While the relevancy and the significance of the statistical evidence is a subissue bearing on the sufficiency of the proof, such evidence alone neither proves nor disproves plaintiff's case.

I

Proximate cause is neither easily defined nor readily understood. Dean Prosser begins his discussion of proximate cause with this disclaimer:

There is perhaps nothing in the entire field of law which has called forth more disagreement, or upon which the opinions are in such a welter of confusion. Nor, despite the manifold attempts which have been made to clarify the subject, is there yet any general agreement as to the proper approach. Much of this confusion is due to the fact that no one problem is involved, but a number of different problems, which are not distinguished clearly, and that language appropriate to a discussion of one is carried over to cast a shadow upon the others.

(Footnotes omitted.) W. Prosser, Torts § 41, at 236 (4th ed. 1971).

*637Confusion is generated by the fact that proximate cause is a uniquely legal concept. It is not synonymous with the concept of cause in a philosophical sense because, hypothetically, an act may cause endless consequences. See Restatement (Second) of Torts § 431, comment a (1965). Proximate cause, however, represents the judicial limitations placed upon an actor's liability for the consequences of his or her conduct. See King v. Seattle, 84 Wn.2d 239, 249, 525 P.2d 228 (1974); cf. Hunsley v. Giard, 87 Wn.2d 424, 434, 553 P.2d 1096 (1976) (liability limited through judicial definition of duty).

The boundaries of proximate cause are not self-determinative. The question is one of law, not fact alone, and it is one that necessarily involves a policy decision. See Pro-bert, Causation in the Negligence Jargon: A Plea for Balanced "Realism", 18 U. Fla. L. Rev. 369 (1965); Green, The Causal Relation Issue in Negligence Law, 60 Mich. L. Rev. 543 (1962). Whether the case goes to the jury or the judge dismisses the claim for a failure to make a case for causation may depend on the actors and the circumstances involved.

Seldom does a rule protect every victim against every risk that may befall him, merely because it is shown that the violation of the rule played a part in producing the injury. The task of defining the proper reach or thrust of a rule in its policy aspects is one that must be undertaken by the court in each case as it arises.

Malone, Ruminations on Cause-In-Fact, 9 Stan. L. Rev. 60, 73 (1956). For example, the standard of proof of causation involving an intentional wrongdoer or joint tortfeasors may often be relaxed, whereas stringent proof requirements have been applied if the plaintiff was partially at fault. Compare Madigan v. Teague, 55 Wn.2d 498, 348 P.2d 403 (1955) (joint tortfeasors found liable) with Scott v. Rainbow Ambulance Serv., Inc., 75 Wn.2d 494, 452 P.2d 220 (1969) (case dismissed because of plaintiff's failure to segregate his contribution to the damages).

Malpractice suits represent a class of controversies where *638extreme caution should be exercised in relaxing causation requirements. See Atkins v. Clein, 3 Wn.2d 168, 100 P.2d 1 (1940). The physician serves a vital function in our society, a function which requires the assumption of a duty to the patient. Yet, his profession affords him only an inexact and often experimental science by which to discharge his duty. Moreover, the tendency to place blame on a physician who fails to find a cure is great. Thus policy considerations do not, on balance, weigh in favor of abandoning the well established requirements of proximate cause.

The majority proposes adoption of the substantial factor test for cases falling under Restatement (Second) of Torts § 323(a) (1965). This was the approach taken in Hamil v. Bashline, 481 Pa. 256, 392 A.2d 1280 (1978); however, application of the substantial factor test in these circumstances is truly novel. Usually the substantial factor test has been applied only in situations where there are two causes, either of which could have caused the event alone, and it cannot be determined which was the actual cause. See Madigan v. Teague, supra. For example, A and B both start separate fires which combine to burn C's house. Either fire alone would have caused the same result, but C cannot prove that "but-for" the negligence of either A or B the house would not have burned. Therefore, to prevent both A and B being relieved of liability, the "but-for" test is abandoned, and the question becomes whether the conduct of A or B was a substantial factor in causing the fire that injured C. Under this test, either A or B could be held liable for the damage.

Except in situations where there are coequal causes, however, defendant's act cannot be a substantial factor when the event would have occurred without it. W. Prosser, at 244. Moreover, the substantial factor test has not been applied when one of the causes of the injury was the plaintiff himself. Hence in Scott v. Rainbow Ambulance Serv., Inc., supra, the case was dismissed because plaintiff failed to segregate her contribution to the damages from that of the tortfeasor; there was no discussion of the tortfeasor's *639conduct in the context of the substantial factor test. Similarly, the substantial factor test should not be applied in the instant case.

II

Furthermore, the instant case does not present evidence of proximate cause that rises above speculation and conjecture. The majority asserts that evidence of a statistical reduction of the chance to survive for 5 years is sufficient to create a jury question on whether the doctor's conduct was a proximate cause of the death. I disagree that this statistical data can be interpreted in such a manner.

Use of statistical data in judicial proceedings is a hotly debated issue. See, e.g., Finkelstein & Fairley, A Bayesian Approach to Identification Evidence, 83 Harv. L. Rev. 489 (1970) (Finkelstein & Fairley I); Tribe, Trial by Mathematics: Precision and Ritual in the Legal Process, 84 Harv. L. Rev. 1329 (1971) (Tribe I); Finkelstein & Fairley, A Comment on "Trial by Mathematics", 84 Harv. L. Rev. 1801 (1971) (Finkelstein & Fairley II); Tribe, A Further Critique of Mathematical Proof, 84 Harv. L. Rev. 1810 (1971) (Tribe II); Dickson, Medical Causation by Statistics, 17 Forum 792 (1982); see also Brachtenbach, Future Damages in Personal Injury Actions — The Standard of Proof, 3 Gonz. L. Rev. 75 (1968). Many fear that members of the jury will place too much emphasis on statistical evidence and the statistics will be misused and manipulated by expert witnesses and attorneys. Tribe I, supra; Dickson, supra; People v. Collins, 68 Cal. 2d 319, 438 P.2d 33, 66 Cal. Rptr. 497 (1968).

Such fears do not support a blanket exclusion of statistical data, however. Our court system is premised on confidence in the jury to understand complex concepts and confidence in the right of cross examination as protection against the misuse of evidence. Attorneys ought to be able to explain the true significance of statistical data to keep it in its proper perspective.

Statistical data should be admissible as evidence if they are relevant, that is, if they have

*640any tendency to make the existence of any fact that is of consequence to . . . the action more probable or less probable than it would be without the evidence.

ER 401. The statistics here met that test; they have some tendency to show that those diagnosed at stage 1 of the disease may have a greater chance to survive 5 years than those diagnosed at stage 2.

The problem is, however, that while this statistical fact is relevant, it is not sufficient to prove causation. There is an enormous difference between the "any tendency to prove" standard of ER 401 and the "more likely than not" standard for proximate cause.3

Reliance on statistics alone to prove proximate cause may lead to unjust results. A simple example will illustrate my point. Assume there are two cab companies in a town; one has three blue cabs and the other has one yellow cab. A pedestrian is hit by a cab, but doesn't know what color it was. In a suit for personal injury, plaintiff wants to admit the statistical fact that there is a 75 percent chance that she was hit by a blue cab. This fact has relevancy; it is admissible. But is it sufficient to prove the blue cab company more probably than not committed the act? No. If this were not the case, the blue cab company could be held liable for every unidentified cab accident that occurred.

Thus statistics alone should not be sufficient to prove proximate cause. What is necessary, at the minimum, is some evidence connecting the statistics to the facts of the case. Referring back to the cab example, testimony that a blue cab was seen in the vicinity of the accident before or after it occurred or evidence of a recently acquired, unaccounted for, dent in a blue cab could combine with the sta*641tistical evidence to lead a jury to believe it was more probable than not that this plaintiff was hit by a blue cab. See Finkelstein & Fairley I.

Thus, I would not resolve the instant case simply by focusing on the 14 percent differentiation in the chance to survive 5 years for the different stages of cancer. Instead, I would accept this as an admissible fact, but not as proof of proximate cause. To meet the proximate cause burden, the record would need to reveal other facts about the patient that tended to show that he would have been a member of the 14 percent group whose chance of 5 years' survival could be increased by early diagnosis.

Such evidence is not in the record. Instead, the record reveals that Mr. Herskovits' cancer was located such that corrective surgery "would be more formidable". This would tend to show that his chance of survival may have been less than the statistical average. Moreover, the statistics relied on did not take into consideration the location of the tumor; therefore, their relevance to Mr. Herskovits' case must be questioned. Clerk's Papers, at 41.

In addition, as the tumor was relatively small in size when removed (2 to 3 centimeters), the likelihood that it would have been detected in 1974, even if the proper test were performed, was less than average. This uncertainty further reduces the probability that the doctor's failure to perform the tests was a proximate cause of a reduced chance of survival.

Other statistics admitted into evidence also tend to show the inconclusiveness of the statistics relied on by the majority. One study showed the two-year survival rate for this type of cancer to be 46.6 percent for stage 1 and 39.8 percent for stage 2. Mr. Herskovits lived for 20 months after surgery, which was 26 months after defendant allegedly should have discovered the cancer. Therefore, regardless of the stage of the cancer at the time Mr. Herskovits was examined by defendant, it cannot be concluded that he survived significantly less than the average survival time. Hence, it is pure speculation to suppose that the doctor's *642negligence "caused" Mr. Herskovits to die sooner than he would have otherwise. Such speculation does not rise to the level of a jury question on the issue of proximate cause. Therefore, the trial court correctly dismissed the case. See Restatement (Second) of Torts § 434 (1965); Scott v. Rainbow Ambulance Serv., Inc., 75 Wn.2d 494, 452 P.2d 220 (1969).

The apparent harshness of this conclusion cannot be overlooked. The combination of the loss of a loved one to cancer and a doctor's negligence in diagnosis seems to compel a finding of liability. Nonetheless, justice must be dealt with an even hand. To hold a defendant liable without proof that his actions caused plaintiff harm would open up untold abuses of the litigation system.

Cases alleging misdiagnosis of cancer are increasing in number, perhaps because of the increased awareness of the importance of early detection. These cases, however, illustrate no more than an inconsistency among courts in their treatment of the problems of proof. See Annot., Malpractice in Connection with Diagnosis of Cancer, 79 A.L.R.3d 915 (1977). Perhaps as medical science becomes more knowledgeable about this disease and more sophisticated in its detection and treatment of it, the balance may tip in favor of imposing liability on doctors who negligently fail to promptly diagnose the disease. But, until a formula is found that will protect doctors against liability imposed through speculation as well as afford truly aggrieved plaintiffs their just compensation, I cannot favor the wholesale abandonment of the principle of proximate cause. For these reasons, I dissent.

Dimmick, J., concurs with Brachtenbach, J.

Dolliver, J.

(dissenting) — This is apparently a case of first impression. As is usually true in such instances, the court is called upon to make a policy decision. The issue before us is whether, when the chance of survival is less than a probability, i.e., less than 50 percent, proof that the *643chance of survival — not the probability of survival — is reduced is sufficient to take the case to the jury.

The majority answer in the affirmative cites several cases in support of this view and adopts the reasoning of Hamil v. Bashline, 481 Pa. 256, 392 A.2d 1280 (1978). I favor the opposing view and believe the reasoning in Cooper v. Sisters of Charity, Inc., 27 Ohio St. 2d 242, 272 N.E.2d 97 (1971), also cited by the majority, is more persuasive. In discussing the rule to be adopted the Ohio Supreme Court stated:

A rule, which would permit a plaintiff to establish a jury question on the issue of proximate cause upon a showing of a "substantial possibility" of survival, in our judgment, suffers the same infirmity as a rule which would permit proof of a "chance of recovery" to be sufficient. While the substantial possibility concept appears to connote a weightier burden than the chance of recovery idea, both derogate well-established and valuable proximate cause considerations. Traditional proximate cause standards require that the trier of the facts, at a minimum, must be provided with evidence that a result was more likely than not to have been caused by an act, in the absence of any intervening cause.

Lesser standards of proof are understandably attractive in malpractice cases where physical well being, and life itself, are the subject of litigation. The strong intuitive sense of humanity tends to emotionally direct us toward a conclusion that in an action for wrongful death an injured person should be compensated for the loss of any chance for survival, regardless of its remoteness. However, we have trepidations that such a rule would be so loose that it would produce more injustice than justice. Even though there exists authority for a rule allowing recovery based upon proof of causation by evidence not meeting the standard of probability, we are not persuaded by their logic. . . .

We consider the better rule to be that in order to comport with the standard of proof of proximate cause, plaintiff in a malpractice case must prove that defendant's negligence, in probability, proximately caused the death.

(Citations omitted.) Cooper, at 251-52. This, it seems to *644me, is a better rule.

The majority states the variations from 39 percent to 25 percent in the decedent's chance for survival are sufficient evidence to "consider the possibility" that the failure of the physician to diagnose the illness in a timely manner was the "proximate cause of his death." This reasoning is flawed. Whether the chances were 25 percent or 39 percent decedent would have survived for 5 years, in both cases, it was more probable than not he would have died. Therefore, I cannot conclude that the missed diagnosis was the proximate cause of death when a timely diagnosis could not have made it more probable the decedent would have survived. "'It is legally and logically impossible for it to be probable that a fact exists, and at the same time probable that it does not exist.'" Cooper, at 253 (quoting Davis v. Guarnieri, 45 Ohio St. 470, 490, 15 N.E. 350 (1887)). It would be pure speculation, given these figures, for an expert, a jury, or anyone else to conclude the decedent would live more or less time within the 5-year period with or without the proper diagnosis.

Two further comments: Factually, many of the cases cited by the majority, including Hamil v. Bashline, do not support its position. In McBride v. United States, 462 F.2d 72 (9th Cir. 1972), the mortality rate was 15 percent for coronary patients admitted to the hospital and 30 to 35 percent for those outside the hospital. Thus, in any circumstance, the probability of survival was over 50 percent and was measurably greater in rather than out of the hospital. In Hamil v. Bashline, supra at 272 n.9, the court stated the testimony observed "a 75% chance of recovery had prompt treatment been administered". In Hicks v. United States, 368 F.2d 626 (4th Cir. 1966), the court observed, "Both of plaintiff's experts testified categorically that if operated on promptly, Mrs. Greitens would have survived, and this is nowhere contradicted by the government expert." Hicks, at 632.

In Wooldridge v. Woolett, 96 Wn.2d 659, 638 P.2d 566 (1981), we held the value of a decedent's shortened life *645expectancy was not recoverable as a separate item of damages in a survival action under RCW 4.20.046. Yet, in the present case the majority is willing to grant recovery, not where there is a direct cause for the shortened life expectancy, but on the more ephemeral basis of a statistical probability entitled "probability of survival".

While these observations may not go to the heart of the majority position, they do make it a bit ragged around the edges.

I believe the position articulated in Cooper v. Sisters of Charity, Inc., supra, is preferable and thus I dissent.

Reconsideration denied July 21, 1983.