ON REHEARING
McFADDEN, Chief Justice.Defendant strenuously urges that this court was in error in its original opinion wherein it was determined that the evidence on the issue of proximate cause is so conclusive as to establish proximate cause as a matter of law. Defendant also contends that as a matter of law the record fails to establish any negligence on the part of the defendant.
First considering the issue of negligence, the trial court made explicit findings of fact, not only in its “Findings of Fact,” but also its written opinion rendered prior to entry of the findings of fact, conclusions of law and judgment. The trial court incorporated this written opinion into its findings of'fact and conclusions of law.
In its written opinion, the trial court found:
“I find that during period (4) there were no antibiotics, that there should have been and that the defendant should have known that there were none. His failure to administer antibiotics during this time must be characterized as a departure from the standard; I further *298find, however, that there was not, during this period, evidence of odor and drainage requiring the opening of the cast and a change of procedure in treatment from that commenced by Dr. Kerby.
“I find that on June 15th the defendant learned of foul smelling drainage and should have immediately seen the plaintiff, opened the cast, taken appropriate tests and administered a broad spectrum antiobiotic different from declomycin until the tests indicated which antibiotic to use His failures in period (5) , were 'a breach of the local standard of care, * * *.”
These two paragraphs of the written opinion find their counterpart in the findings of fact, as follows:
“VII. .On June 9, 1961, the Plaintiff’s supply of anti-biotics was exhausted. The Defendant knew, or should have, in the exercise of the standard of medical practice in this community, known of this fact. Good practice demanded that anti-biotic .therapy continue from this date for at least another ten days but the Defendant prescribed no anti-biotics and supplied none to the Plaintiff. This was a departure from the standard of medical practice in the community.
“VIII. On June 15, 1961, the wife of the Plaintiff telephoned the Defendant that the cast around the site of the fracture was getting moist and there was an , odor connected with it, and that on the previous day the Plaintiff had run a temperature of 99 degrees. Good medical practice required the Defendant at this time to see the Plaintiff, to window the cast or otherwise subject the wound to observation, to take appropriate tests to determine the proper anti-biotic to administer to control the infection and to administer a broad spectrum anti-biotic different from declomycin until the tests indicated the proper anti-biotic to use. 'His failure to do this was a departure from the local medical standard of care.”
Re-examination of the record herein discloses that these findings of fact are supported by competent, substantial, ’ although conflicting testimony, and hence are binding on this court. Durfee v. Parker, 90 Idaho 118, 410 P.2d 962; King v. MacDonald, 90 Idaho 272, 410 P.2d 969; Meridian Bowling Lanes, Inc. v. Brown, 90 Idaho 403, 412 P.2d 586.
On the issue of proximate cause, the trial court stated in its findings of fact: .
“The care or lack of care by the Defendant for the Plaintiff was not established to be the proximate cause of the loss of the Plaintiff’s leg.”
’ In its written opinion, the trial’ court stated: •
“The fact, I find, is that while infections of this sort are sometimes uncontrollable, they can ordinarily be controlled if treated properly. It is not to be expected that a person with this type of injury and infection will lose his leg. The incidents of amputation must certainly be far smaller than the defendant and another witness suggest (50%); they are not more than the 20% Dr. Terhune suggested and quite possibly considerably less. It .would not be difficult to hold the defendant responsible if he had had the plaintiffs care during, the entire course of the treatment. However, he did not.” (Emphasis added.)
“* * * There is evidence'that proper care over the entire period of treatment- could have been expected to produce different results, but -there, was none that proper care during the time of defendant’s culpability would have.”
The trial court had previously found the defendant guilty of negligence, first in ’failure to continue antibiotic therapy, and secondly in failure to window the cast and take appropriate tests to determine the proper antibiotic to administer. Both of these findings - are directed to the failure of defendant to take steps necessary to control the infection.
*299Dr. Nelson, the orthopedic specialist who amputated plaintiffs leg testified:
“Q. Well, does it mean anything to you, Doctor, that the patient came to you, or at least was admitted to the hospital by you, on the 19th day of June, and on the 26th day of June you amputated the leg?
“A. Yes.
“Q. What would that indicate?
“A. Well it would indicate that there was reason for amputation.
“Q. What would that reason have been ? What was the reason?
“A. Apparently the infection.
“Q. * * * Can you recall, Doctor, why you amputated the leg ?
“A. Apparently because of infection.
“Q. It was uncontrolled?
“A. Yes.”
Defendant himself acknowledged that the probabilities were that if sensitivity tests had been taken and those antibiotics administered, which were disclosed as able to control the infection the particular infection wotild not have been uncontrollable.
The trial court in its written opinion quoted from Reinhold v. Spencer, 53 Idaho 688, 693, 26 P.2d 796, 798, as follows:
“The rule would seem to be that respondent was not required to prove his case beyond a reasonable doubt, nor by direct and positive evidence. It was only necessary that he show a chain of circumstances from which the ultimate fact required to be established is reasonably and naturally inferable.”
The trial court in effect did find proximate cause from the chain of circumstances. However, because the defendant did not have the full care of plaintiff, the court concluded there was no proof of proximate cause. In Pigg v. Brockman, 85 Idaho 492, 381 P.2d 286 (1963), this court held that there can be more than one proximate cause of an injury. Therein, this court quoted with approval the following statement from Riddle v. Artis, 243 N.C. 668, 91 S.E.2d 894, as follows:
“ ‘It is elemental that there may be two or more proximate causes of an injury. These may originate from separate and distinct sources or agencies operating independently of each other; yet if they join and concur in producing the result complained of, the author of each cause may be held liable for the injuries inflicted, * * ” 85 Idaho 501, 381 P.2d 291.
The negligence of the defendant concurred in the final result, and the trial court was in error in its conclusion that a causal relationship was not established.
It is asserted by defendant that there is conflicting testimony which bars this court from consideration of this issue. Defendant points to the testimony of Dr. Kelly:
“Q. Dr. Kelly, based upon the evidence that you have — or the facts you have heard of this case, do you have an opinion as to what was the cause of the loss of this foot and portion of a leg of Mr. Formont?
“A. Well, I think the reason he lost his leg was due to the severity of his injuries. He had torsion of his vessels, he had embarrassment of circulation, he had a lot of soft tissue injury, and, of course, he had infection. But the reason he lost his leg was because he had such a severe injury and no blood supply practically was left to that portion of that extremity.”
Dr. Kelly testified that he had never seen the injury, and had never discussed the case with either Dr. Kerby or Dr. Nelson. The opinion given by Dr. Kelly quoted above, was not given in response to a hypo*300thetical question, and was not based on his own personal knowledge of the case. All he knew of the case was that he had heard in the courtroom, and what he had obtained in discussion with others, which discussions were outside of the courtroom. In Evans v. Cavanagh, 58 Idaho 324, 73 P.2d 83 (1937), this court held that the testimony of a physician called as an expert witness, was not entitled to be given any weight even though it was admitted without objection, when the testimony was not based on a hypothesis of facts relied on by the party propounding the question, hut involved determination of truth and reliability of other witnesses. In explanation of the reason for such holding, this court quoted from People v. McElvaine, 121 N.Y. 250, 24 N.E. 465, 18 Am.St.Rep. 820, as follows:
“ ‘We cannot doubt but that this question was improper. The witness was thus permitted to take» into consideration all the evidence in the case given upon a long trial, extending over nine days, and, upon so much of it as he could recollect, determine for himself the credibility of the witnesses, the probability or improbability of their statements, and, drawing therefrom such inferences as, in his judgment, were warranted by it, pronounce upon the sanity or insanity of the defendant. It cannot be questioned but that the witness was by the question put in the place of the jury, and was allowed to determine, upon his own judgment, what their verdict ought to be in the case.’ ” 58 Idaho 332, 73 P.2d 86.
See also: American Coal B. Co. v. Minneapolis, St. P. & S. S. M. Ry. Co., 41 N.D. 381, 170 N.W. 568 (1919); Buckeye Cotton Oil Co. v. Cheraw Ginning Co., 142 S.C. 247, 140 S.E. 581, dissenting opinion (1927); United States v. 13.40 Acres of Land in City of Richmond, 56 F.Supp. 535 (D.C.Cal.1944); Rogers on Expert Testimony, 3rd Ed. 1941, § 153, p. 362; Wigmore oil Evidence, 3rd Ed. 1940 § 681 (b).
It is our conclusion that the opinion of Dr. Kelly was not entitled to be considered as presenting any conflict within the rule that when there is competent, substantial, although conflicting evidence, findings of fact are binding on this court.
Subsequent to release of the^ original opinion in this case, KNUDSON, J., retired, and SPEAR, J., was appointed to fill the vacancy thus created. The original opinion written by KNUDSON, J., is adopted as the opinion of the majority of this court as now constituted.
The judgment is reversed and the cause remanded with instructions to enter judgment for plaintiff in such amount as the court shall determine to have been established as plaintiff’s damages. By reason of the fact that the district judge who initially tried this case has since resigned from office, the trial judge who hears this cause may reopen the case and permit the introduction of such evidence as the court deems proper tending to establish the amount of damages recoverable by plaintiff.
Costs to appellant.
TAYLOR and SPEAR, JJ., concur.