¶1I concur with my brother Manning in the conclusion that there was no error in the rulings and proceedings-below. But, so far as relates to the exclusion of Blumerick’s testimony concerning the capacity of the testator, I think there were good reasons for the decision beyond those relating to the mere form of the question, which is not in itself to my mind very conclusive.
¶2Doctor Blumerick was introduced apparently as a medical expert, to give opinions not supposed to be receivable from others. Undoubtedly there are many cases in which medical witnesses can do this. They may sometimes, where a question arises upon the proper scientific conclusions depending on facts sworn to by others, give their opinions upon a hypothesis presented to them, as to what such facts denote. Before doing so, however, the witness must be examined as to his qualifications as an expert. But when he is examined concerning facts which have occurred under his own observation, and his opinion is required concerning the proper inferences from those facts, he occupies, as to the facts themselves, the same position with all other witnesses, although there may be some questions arising out of the facts which he can answer and which others can not. Upon questions of mental capacity even non-professional witnesses may give evidence, not only of specific facts and conduct falling under their own observation, but also of the impression they derived at the time, involving to some extent matters of opinion. The difference between them and those who in addition to being eye witnesses are also experts, is, that there may be peculiar indications which the latter-understand better, and concerning which they can express an opinion as scientific deductions, and not wore common sense inferences. But neither class *162can be allowed in any case to give an opinion upon mental capacity or condition, without first showing the circumstances and facts upon which that opinion is based. This is necessary for two reasons: First, it is necessary in order to enable other experts to determine whether the opinions expressed by the witness are correct, and to enable the parties to contradict them if wrong: Second, it is necessary in order that, if an opinion is given on a mistaken or perverted statement of facts, the truth may be elicited from others to destroy the foundation of the conclusions. And a third reason might be mentioned, which is that the Court and jury may know from his opportunities what means the witness had of forming any opinion at all. These are rudimentary principles which can not safely be departed from.
¶3It is certainly very far from clear that in such a case as the one before us there was any room for the evidence of experts. The previous evidence of Blumerick — so far as it went — tended to negative any thing like insanity, and referred only to weakness arising from natural decay, and age. Without undertaking to lay down any inflexible rule, it certainly must, as I think, be very rarely true that experts can in such eases give a jury more light than can be derived from other intelligent eye witnesses. Such was the view taken in Dewitt v. Barly, 17 N. Y. 340; and such is the result of common experience.
¶4In the case before us, Dr. Blumerick was asked, from what he saw on a certain occasion several months before the death of Mudge, what was the mental capacity of the latter. He had given no testimony whatever concerning any facts or appearances. It did not. appear from Ms evidence whether his attention had been called to this particular subject. In short he had stated no fact whatever which either a jury or another witness could apply or test. While there are many cases in which a want of capacity three months before a will is executed must indicate a continued incapacity, there are others which *163would not. Until it is known which of these appearances were relied on, -it could not well he determined whether an opinion — if otherwise competent — ought to be received in evidence. And until the facts were shown, it could not be determined whether the witness was competent to form any opinion whatever, or whether there was room for any inferences not within the unaided good sense of the jury.
¶5Had the witness been fully examined concerning his. means of observation, and also concerning the facts he actually observed, it is possible that the question put, although somewhat loo broad in form, might not have been legally objectionable; and it does not seem to have been objected to on this account. But, standing alone, it was certainly immaterial what opinion any person had formed upon the condition of the deceased, because there was no legal basis shown on which it could be rested.
¶6I concur in sustaining- the judgment.
¶7I concur with my brethren that the judgment should be affirmed. The question put to Dr. Blumerick was properly overruled, both because it was incompetent — the question at issue not being of mental capacity merely— and also because he had not shown that intimacy of knowledge of Mudge and of his capacity at the time of making the will which would enable him to testify either as an expert or in any other capacity. How far the testimony sought to be obtained from him is admissible, and under what circumstances, are questions upon which Courts somewhat differ; and I do not deem their consideration necessary, so long as the witness was not shown competent to give-it under any rule.
¶8Judgment affirmed.