Page:Popular Science Monthly Volume 26.djvu/621

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ROM time to time within the last few years, and perhaps for a longer period, comments have been made in the daily secular press, and occasionally in the medical journals, in reference to the testimony of medical experts, which were anything but flattering to medical men. These comments have, in most cases, had reference to their testimony as experts in cases of alleged lunacy, or in cases involving the question of moral responsibility. They have been charged with ignorance, incompetency, inconsistency, and in some cases with venality. It has been said that their opinions are purchasable.

In support of these grave charges the reader has been referred to the fact that an equal number of eminent experts can usually be found to testify on either side, and that in their testimony they often differ from each other irreconcilably. In other cases no evidence is offered to sustain the charges, except the fact that the opinions of the writer and of the public differ from that of the expert.

In what I shall have to say upon this subject I propose to confine myself to those examples in which the question involved is one of mental capacity and responsibility, as being that in which medical experts have been most often and most severely criticised. To a certain extent, however, you will observe that the arguments employed will apply to expert testimony in any other department of medicine or of science.

1. Medical men, whether they be specialists in the study of mental diseases or not, in the differentiation of the class of diseases now under consideration, labor under peculiar difficulties. There are many mental disorders which are unaccompanied with any recognizable abnormal physical conditions of the brain; that is to say, in which there are no structural lesions of the brain cognizable during life, or which can be satisfactorily demonstrated in the autopsy; and there are many in which the mental alienation can not be fairly traced to any lesions in any other part of the body. The number of these examples may hereafter be found to be smaller than is now known, but for the present the fact is as I have stated. That a functional disturbance of the brain exists in such cases is self-evident; but for aught we know this may be due to some slight molecular, chemical, or vital changes in the nerve-cells of the gray matter of the brain or of a group of cells, not denoted by any peculiar physical signs during life, and which can leave no possible traces after death. To cause mental