Page:Popular Science Monthly Volume 72.djvu/478

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involved in either of these two associated tests; and the man who distinguishes himself in both may, in ordinary life, with his senses and his intellect in their normal state, be a far worse observer and a far worse reporter of the things going on around him than the man who is either too indifferent or too slow-witted to bring his mental and physical faculties to bear adequately upon the artificial test.

It is far from being the purpose of this paper to cast discredit on the methods of experimental psychology. On the contrary, the writer feels that the advance made by that science has been among the most interesting and important of the scientific developments of the past three decades. In Professor M√ľnsterberg's succeeding paper, "The Third Degree," for example, are to be found a number of illustrations of the remarkable results that have been obtained by the methods of experimental psychology. The account of them given by the distinguished professor with that skill and attractiveness of which he is a rare master, while as interesting as a romance, is full of convincing force. The questions there discussed have at once intense theoretical interest and great practical importance; but there is this difference between them and the questions at issue in the paper I have been criticizing: In worming out of a suspect, or a hysterical patient, the secret he is endeavoring to guard, the thing under examination by the expert is highly definite. It is something in the actual contents of the subject's mind or in his emotional susceptibility on certain definite matters. The study of his reaction-times, association-times, etc., has been shown to furnish astonishingly definite information on these specific things. The point made in the present paper is simply that no such case has been made out in the much broader, looser, more varied and more intangible region covered by the question of the trustworthiness of every-day human observation; that the indictment brought against such observation, not so much by the exact letter as by the whole tenor of Professor M√ľnsterberg's article, is not sustained by his instances; and finally that, so far as regards the discrimination of trustworthy from untrustworthy witnesses (truthfulness aside) as to the affairs of ordinary life, the investigation by expert psychologists, in order to be entitled to authority, would have to be vastly more comprehensive and vastly more able than there is any practical possibility of commanding. That there are special classes of cases in which the expert's investigation of a witness would be of value is certain, but the scope of his usefulness must be regarded as severely limited. So far as the ordinary run of things is concerned, the present homely procedure, imperfect as it is, is to be preferred to a system in which, over and above the question of the trustworthiness of witnesses, there would be injected into every case of importance the further and at least equally puzzling question of the trustworthiness of the tests employed by the psychological expert.