j gEBVi0ES. or¿Etaarynskffl presumed. I. The court instructed the jury as follows: •(3.) “The law requires of a physician and surgeon in the treatment of his patients the use of ordinary skill a:n<^ diligence only, the average of that possessed the.profession as a body, and not of the thoroughly educated only, having regard to the improvements and the- advanced state of the profession at the time of the treatment; and if you find that the defendants or .either of them employed the plaintiff as a physician and surgeon to1 treat their mother and perform a surgical operation on her, and you find that the plaintiff did, as a physician and surgeon, treat 'the mother of defendants and perform a surgical operation, and did so with the skill above stated, then he is entitled to recover the reasonable value of the services so rendered; and if the jury do not find that the plaintiff so treated the mother 'of defendants and so performed the surgical operation on helas above stated, then the jury will find for the defendants.” (6.) “In this case the action is brought to recover compensation for services rendered by plaintiff as a physician and surgeon, and the defendants claim as a defense thereto that such service was not rendered with such skill as is required by law. As to this issue the burden rests with the plaintiff to show by ■a fair preponderance of evidence that the service rendered by 'him was performed with the skill required as set forth in instruction No. 3.” This last instruction is erroneous. If it was necessary that the plaintiff should prove these facts, then ■every mechanic, citizen or husbandman, in order to recover in ’any case, must aver and prove that the labor for which he ■seeks compensation was performed in a reasonably /skillful *627manner. The law does not impose such burden. There is no presumption of the law that professional men or mechanics do not possess sufficient skill for the proper discharge of the duties of their various employments, or that, possessing such skill, they are too negligent or too dishonest to exercise it. Suppose the defendants had not by way of answer alleged that plaintiff .did not possess or did not exercise reasonable skill in the treatment of the case. Then the plaintiff would have made out a ¶rima facie case by proving his professional character, his employment by defendants, the rendition of the services and their value. But the fact that defendants make this allegation in their answer cannot affect the amount of proof necessary .to constitute a prima facie case. The defendants have asserted that plaintiff did not possess or did not. exercise reasonable skill. As to this allegation the defendants assumed the affirmative of the issue. The obligation of proving any fact lies upon the party who substantially asserts the affirmative of the issue. Greenleaf on Evidence, § 74 and notes.
_. _. ■ conaltton of . patient. II. The plaintiff introduced evidence tending to show the pecuniary condition of defendants, and that the ability of the patient to pay sometimes forms an element in the am0UI1t °f the charge. Respecting this the court charged as follows: “The facts of the circum,.stances of the parties subject to be charged as defendants .herein do not constitute an element in fixing the value of the .services. And, if any evidence has been offered on this subject, the jury should entirely disregard it as the right to recover an amount that might be recovered on the financial .worth or standing of the defendant.”
The plaintiff assigns the giving of this instruction as error. The instruction is, we think, correct. There is no more reason • why this charge should be enhanced on account of the ability . of the defendants to pay, than that the merchant should charge ■ them more for a yard of cloth, or the druggist for filling a ■ prescription, or a laborer for a day’s work. It is true a physician in general practice will often be called upon to treat indigent persons from whom he will not. be able to recover the value of his. services; He'may take this.into account and reg*628ulate his charges with reference to that fact, just as a merchant may take into account probable bad debts in fixing his per centvm of profit upon his goods. But the value of a service depends upon the difficulty of rendering it, and the skill required in its performance, and, sometimes, upon the results accomplished, and not upon the riches or the poverty of the person for whom the service is performed.- If the ability to ■pay determines the reasonableness of a charge, then the richer ■a man is the more he should pay for any service. No such rule of charge can be recognized or countenanced by the law.
III. The plaintiff, when on the stand in chief, was asked on cross-examination if he had not stated to certain witnesses that the patient’s bowel had sloughed off from place of hernia downward, or from hernial ring downward. lie answered that he did not remember of stating the same, and had not stated the same to anybody. The defendants introduced witnesses who testified that plaintiff had made oral statements to the effect that the lower part of the bowel of the j>atient had sloughed away since the operation was performed, and that said patient could never have a natural passage. Thereupon plaintiff was called as a witness in his own behalf, and was asked his understanding of the import of the term “ lower part of the bowel,” if the same was used by him, and as to the true meaning of said term and the other oral terms in the connection as used by him, if the same were used by him. The plaintiff, who had testified that he was a regular graduate of a medical college, and for years had been engaged in general practice of medicine and surgery, was also asked what a surgeon or physician would understand by the term “ lower part of the bowel had sloughed off,” as applied to or spoken of a person who had been operated upon for strangulated femoral hernia, and gut found mortified. To these questions the defendants objected, and the court sustained the objection. The plaintiff excepted to this ruling, claiming the said term or phrase referred only to the lower part of the bowels in the hernial sack. The court, however, ruled it would permit plaintiff to inquire whether the term “lower part of the bowels ” has a technical meaning differing from its ordinarily *629received meaning, and no further. This action of the court was erroneous, and prejudicial to the plaintiff. The testimony-introduced by defendants, in addition to its tendency to 'impeach the plaintiff, was calculated to show that he was ignorant of the patient’s real condition. The plaintiff should have been permitted to show to what he referred in the language imparted 'to him. See Mickey v. Burlington Ins. Co., 35 Iowa, 174 (181). For these reasons the judgment is
Reversed.