As shown by its journal entry the court of appeals reversed the judgment of the trial court solely on the ground of “error in the charge of the court to the jury; no other error appearing in the record.”
The record is unusually large. There was, however, very little contention as to the situation or the occurrences on the day of the injury. It is conceded that the plaintiff became blind more than a year afterwards, and the most important issue of fact, the one around which the contest was chiefly waged, was whether the blindness was caused by the injury received on the day of the accident.
The effort of the plaintiff was directed to the maintenance of his position that the injury received at the bench was the direct and proximate cause of his ultimate blindness in both eyes.
*242The contention of the defendant was that the blindness of the plaintiff resulted from causes wholly disconnected with the injury referred to in the petition. The greater part of the testimony of the defendant was introduced in an effort to show that the blood of the plaintiff was affected by a syphilitic taint, either hereditary or acquired, and that this was the cause of the blindness. The trial court and the court of appeals in the performance of their duty to examine and weigh the evidence did not sustain the contention of defendant that the verdict was against the weight of the evidence, or excessive.
On the issue as to the cause of the ultimate blindness of the plaintiff a number of physicians were called by the parties as experts. The burden was upon the plaintiff to show the legal relation of cause and effect between the injury and thé blindness; and the length of time between the injury and the ultimate blindness in both eyes naturally impressed upon both parties the great importance and value of expert testimony.
,By far the most important, and in truth it may be said to be the crucial, difference between the parties throughout related to the claim of the plaintiff that the sight of his left eye “was entirely gone, or almost entirely gone from the time he was struck.” The hypothetical question put by defendant’s counsel to the physicians called by them made no reference to this claim. They were not asked to answer as to that hypothesis. In this connection defendant’s counsel complain of the following portion of the charge-: “Hypothetical *243questions are drawn so as to embrace all of the symptoms, all of the things about the injury — in this case, about the blindness — starting from the time of the injury, starting back of that, may be a man’s full life, taking up through the injury, stating in the question all of the facts which would throw light upon the question, and then asking the physician, his physician, as. to whether it was probable or likely that the accident occurred or how the accident might have occurred.”
Counsel urge that under that portion of the court’s charge the jury would be authorized and required to disregard the opinion of all of defendant’s experts, for the sole reason that the question did not embrace the one alleged fact referred to, and that this was error. We think this is too narrow a view of the language. It was, as claimed by defendant, proper for him to omit from his question the statement that the plaintiff became blind or almost blind in his left eye immediately after the accident, because he earnestly contended that the plaintiff had not then, or soon after, become blind in his left eye. But plaintiff contended exactly the opposite. That was a question to be determined by the jury from a preponderance of the evidence. If the jury should find for the defendant on that issue, the force and value of the answers of the experts to his question might be very great; but if the jury should find upon that issue for the plaintiff, manifestly the absence of this important fact from the question of the defendant would very greatly weaken the value of the opinions expressed by the experts. Counsel *244on each side were entitled to include in their hypothetical questions such facts as they claimed were shown by the evidence. The evidential facts are generally in dispute and it cannot be known where the jury will find the preponderance to be. Each party has the right to show the scientific con-. elusions to be drawn from the facts as he claims them to be, subject to' the contingency that the jury shall find the facts to be as stated.
The chief complaint made against the chargé of the court concerned the following part of it, and it is this portion upon which the court of appeals based its judgment of reversal: “So, if there was any material fact which it was necessary to have for the physician or expert to base his opinion, and that fact was not true or not proven, then, of course, the expert’s opinion'would necessarily fall because the fact was not there upon which to base such an opinion.” And also this: “They simply make their answer, base their answer upon the facts that are submitted to them in the question and, if there is any important fact, material fact, that is in the question which- is not true, that is not proven to be true, then the question that the doctor makes his opinion upon, gives his opinion upon that question, then he has given it upon such a statement of facts,” etc. The use of the words “material” and “important” is claimed to be erroneous.
It must be kept in mind that the expert testimony related to and was important upon the question whether the blindness of the plaintiff resulted from the injury received on the day of the acci*245dent. The proximate cause of a result is that which in a natural and continued ■ sequence produces the result and without which it would not have happened. The burden was upon the plaintiff to show that his blindness resulted in a natural and continued sequence from the blow and without which it would not have resulted.
The court, at the request of the defendant, before argument charged .the jury as follows: “I say to you that the opinions of such experts based upon facts so assumed are of no value, unless all of the assumed facts forming the basis of such opinion are found by the jury to be true, and that if you find that any fact assumed in the hypothetical question put to any such medical witness is untrue, then it will be your duty to disregard the opinion expressed by such medical expert.” And also the following: “The plaintiff called as a witness one Dr. William H. Phillips and propounded to him a hypothetical question in which it was stated as a fact that from the time the plaintiff’s left eye was struck on July 19th, 1912, the sight of his left eye was entirely gone, or almost entirely gone.
“I charge you that unless you find from a preponderance of the evidence that the sight of the plaintiff’s left eye was entirely gone, or almost entirely gone, from the time he was struck on July 19th, 1912, then you should entirely disregard the opinion expressed by said witness in answer to such hypothetical question.”
The proposition asserted by the defendant and approved by the court of appeals is quoted from *246General Convention of New Jerusalem Church et al. v. Crocker et al., 7 C. C., 327, 333, as follows: “Logically, if any facts which the evidence does not establish are assumed as a part of the foundation of the expert opinion, the opinion is of no value for the purposes of the case. The theory upon which opinions of experts are admitted is, that the witnesses have knowledge not possessed by the jurors, which forms a foundation for safe conclusions in a particular case.”
It is urged that the charge of the court permitted the jury to determine what facts were material or important and what were not so, and that this is not the function of the jury. A fair statement of the view which supports the contention made by the defendant in error is found in the case of Burk v. Reese et al., 143 Ia., 496, cited by him. In that case the supreme court of Iowa had before it a charge in which is found the following language: “Should such assumed facts not be supported by the evidence, or should it turn out that such hypothetical questions are in important particulars incorrect, unfair, partial and untrue, no weight whatever can be given to the opinion founded thereon.” The court say: “We are constrained to hold that, under the settled rule of our own cases, this instruction cannot be upheld. It leaves the jury to say for itself what facts embodied in the hypothetical question are of so little importance that a failure to establish them by the evidence may be disregarded, and the answer still be allowed weight in reaching a verdict. This we have frequently held to be reversible error.”
*247Substantially this view has been, supported in Fisher v. Travelers’ Ins. Co., 124 Tenn., 450; People v. Foley, 64 Mich., 148, and Dudley v. Gates, 124 Mich., 440.
The opposite view is stated in 1 Wigmore on Evidence, Section 680, thus: “It follows as á necessary part of the theory, that if the premises are ultimately, rejected by the jury as untrue, the testimonial conclusion based on them must also be disregarded. This is plain enough where a witness has claimed to have personal observation and is disbelieved. It is only where his testimony is based on hypothetical data that the same result needs to be emphasized.- But the failure which justifies rejection must be a failure in some one or more important data, not merely in a trifling respect.” This proposition finds support in Taylor v. Taylor, 174 Ind., 670; Grand Lodge I. O. M. A. v. Wieting, 168 Ill., 408, 3 Syl.; People v. Vanderhoof, 71 Mich., 158, 176, and Blough et al. v. Parry et al., 144 Ind., 463.
We think there is force in the contention that the jury should' not be led by the instruction of the court to consider what are material and what are immaterial facts embodied in a hypothetical question. They are to act upon the evidence submitted to them and upon all of the evidence. The expert is a scientific person, and it cannot be known to the jury what he regards as material or immaterial in making up his answers. The correctness of this is sufficiently demonstrated by the testimony of the expert physicians in this case. The onty sound theory upon which the expert’s opinion is *248admitted at all is that he has the knowledge, training and experience with which to form a, better opinion on a given state of facts than one not so well equipped. On the other hand there should be no such instruction as would invite a capricious search by the jury into features which might be wholly unimportant and unessential, thereby leading them to reject the testimony of. an expert of ability and high character, whose opinion had been formed after a conscientious and successful effort to arrive at true conditions.
The supreme court of Iowa, which has declared and enforced the strict rule above stated in a number of cases before it, said in a very recent case, Peterson v. Brackey, 143 Ia., 75, 82: “In the case last cited an instruction is criticised which left it to the jury to say whether the statements of fact assumed in the hypothetical questions were ‘substantially’ correct, but it is not intimated that the case would have been reversed on this ground. It certainly is not necessary that the facts assumed in a hypothetical question shall be proven in every material detail-to the dotting of an ‘i’ and the crossing of a ‘t,’ and, while the court might properly have omitted the word ‘substantially,’ we can not believe that the jurors were misled by its use.”
Take for example the hypothetical question put by the defendant’s counsel themselves in this case. The question covers some seven pages of the' record and embodies the facts which defendant’s counsel believed to be shown by the preponderance of the testimony, concerning the cause of plaintiff’s blindness. Now it would be manifestly unjust to *249the defendant to so instruct the jury as to lead them to reject the opinion of the four physicians of recognized position whom the defendant had called, simply because they might find one assumption or statement of fact in the seven pages, however unimportant, to be not established by the preponderance of the evidence, although the counsel for the defendant had included the statement in his question in the full belief of its truth. Such a rule would be too technical and would not contribute to the substantial administration of justice. But if it be conceded that the use of the terms “important fact” and “material fact” by the trial court in its charge in this case is properly open to criticism, we think it clear that it could not have been prejudicial to the defendant.
As already stated, the plaintiff propounded to the experts called by him a hypothetical question in which it was stated as a fact that from the time plaintiff’s left eye was struck the sight was entirely gone, or almost entirely gone; and, as shown, at the request of defendant’s counsel the court charged the jury that “unless you find from a preponderance of the evidence that the sight of plaintiff’s eye was entirely gone, or almost entirely gone, from the time he was struck, you should entirely disregard the opinion expressed by said witness in •answer to such hypothetical question.”
It is perfectly clear from the record that the matter of the blindness or almost blindness in the left eye immediately after the accident was the crux of the case. That was the material, the important, fact in dispute. The jury were distinctly *250told that if the plaintiff failed to establish this claim they should disregard the testimony of the plaintiff’s experts.
The hypothetical question of the plaintiff was very much shorter than that propounded by the defendant. In the defendant’s hypothetical question no reference whatever was made to the claim or assumption that the plaintiff became blind or almost blind immediately after being struck.
The physicians called by defendant at once conceded on cross-examination that if it were shown that blindness-in the left eye followed soon after the blow, an entirely different question would be presented.
On reflection it will be seen that any error of the court in the use of the words “material” and “important” did not result in prejudice to the defendant, but was rather in his favor. Because the jury might have found that in defendant’s hypothetical question of several pages there was included some assumption which was not sustained and yet under the instruction given if the jury regarded it as not “important” or “material” they would disregard that assumption. They would not treat the expert’s “opinion as of no value for the purposes of the case” but would give to the opinion such weight as they believed it to be entitled.
The paramount query is not, Did the hypothetical question include elements not proven by the evidence, the importance and materiality of which the jury were permitted to speculate upon? but, 'Was there omitted from the hypothetical question *251of defendant a concededly material and determinative assumption, which was included in the hypothetical question of plaintiff, and as to which the jury were instructed at request of defendant, that unless they found that plaintiff’s assumption was sustained by the evidence they should disregard the opinion of plaintiff’s expert? And although this requested charge was given before the argument* it was in no degree modified by what was said in the general charge.
The court of appeals well said, “Here, then, were two well defined and distinct theories of the case and the record shows that they were zealously, thoroughly and adequately brought before the jury on the respective sides of the controversy, and it is due to counsel to say the jury were made to understand each theory to the remotest point. Right or wrong in result, what the jury did was not by reason of not being informed as to what each party claimed and was contending for, so far as the case depended on matter of fact.”
We are convinced that the strongly corroborated testimony that plaintiff' had always been free from eye trouble prior to the injury, taken in connection with the vastly important testimony of plaintiff that he became blind in the left eye soon after-wards, was regarded by the triers of the facts as entitled to great weight.
We think it clear that the learned court was in error in regarding the use of the words referred to by the trial court in its charge to the jury as conclusively prejudicial error.
*252The judgment of the court of appeals will be reversed and that of the common pleas affirmed.
Judgment reversed.
Nichols, C. J., Donahue, Wanamaker, Newman and Matthias, JJ., concur. Jones, J., not participating.