[9] There is a minor problem of psychological interest in regard to the fraud apparent in these manifestations, that is worthy of consideration: namely, the motives for such fraud. That greed for gain and notoriety constitute two of the main inducements is obvious enough; that the latter is a far more widespread and variable mental inducement than we ordinarily realize, has been shown by the cases in which fraud has been detected. In addition we must recognize the existence of deception as the expression of a deep-seated instinct abnormally present in not a few persons. It is deception for the love of imposing upon humanity, mingled somewhat with a love of the conspicuousness and interest which the deceiver's position brings with it; and this often exists where the motives for it cannot be accurately determined. Cases of deception on the part of children, on the part of those who present suspicions of the hysterical temperament, and cases of so-called disinterested deception, have been collected in sufficient number to make the criticisms which are advanced against professional mediums quite as cogent in the case of unpaid and private mediums. I may refer to the discussion of the subject by Mr. Podmore. _Studies in Psychical Research_, p. 185, sqq. HYPNOTISM AND ITS ANTECEDENTS Important periods in the history of science are as likely to be characterized by changes in attitude towards the accepted body of knowledge, as by the extension of its realm through new discoveries. The contrast between the undeveloped and the advanced stages of a science is as well realized by noting the totally different mode in which facts are viewed, as by observing the vast increase in the range of recorded fact. The alchemist and the chemist have far more in common in the way of operations and material than in their conceptions of the purposes and the method of their pursuits. The astrologer and the astronomer are again most characteristically differentiated by their motives and point of view; both observe the positions of planet and star, and calculate orbits and phases and oppositions; but nothing is more absurdly irrelevant to the astronomer's purpose than the hope of predicting the fortunes of men. A more modern example of a similar relation is that between phrenology and the physiological doctrine of the localization of functions in the brain. And alchemist, astrologer, and phrenologist have this in common: that they aimed at immediately practical ends. The one hoped to create wealth, the other to foretell and control fate, and the third to insure success by discovering the earmarks of natural gifts. They distorted the facts of nature, and in the narrow pursuit of a practical goal, substituted for realities their own fanciful theories, or the elaborations of their defective logic. Science advances most favorably when the best energies are devoted to a comprehension of fundamental principles and to the accumulation of