PSYCHICAL RESEARCH. 506 PSYCHICAL RESEARCH. treme delicacy of sensibility' in a sensitive nerv- ous system is ilseh' responsible for much that passes for thought-transference; secondly, be- cause the precautions neces.sary to eliminate such possibilities have not as a rule been taken in the seemin«;ly successful experiments, and proper conditions frequently are dillieult to se- cure: thirdly, because the nsual methods of per- forming such experiments leave the way open for unconscious exagf,'eration and misinterpreta- tion, as well as for the unconscious indication of hints to the percipient. The experimenters have taken into account all of these dilliculties. Yet, in the o])inion of many whose judgment is en- titled to great weight, the accumulated evidence does not justify, even provisionally, the enter- tainment of a 'telepathic' hypothesis. The telcjiathie hypothesis does not rest its case upon experimental evidence alone, however. It presents an enormously extensive body of wit- nesses to the telepathic sending of hallucinations or presentiments, many of them having direct personal significance to those concerned, and an unusual number of them being connected with the moment of death or danger to one of the persons involved in the hallucination. The ))ro- portion of the recorded cases that contain a ver- ifiable coincidence of event and presentiment is, on the wliole, small. An elaborate census of hallucinations has been gathered by the society, and sets forth the relatively lai'ge occurrence of such hallucinations among normal persons in apparent good health. The elimination of coin- cidence is a vital point. The doubtfulness of critics is increased by the consideration that an intense interest in i)resentinients may induce the habit of noticing and recording them, thus in- creasing their relative fre(inency and the oppor- tunity for apparently luiexplainable coincidence; further by the dominant tendency to note and be impressed by favorable instances and not to notice the vastly larger number of unfavorable ones. Other investigations of students in psy- chical researcli relate to the asserted manifesta- tion of the spirits of the departed in the affairs of this earth, mainly through individuals known as 'mediums.' Here again the evidence falls into an experimental and an observational group. The eypcrimental evidence is that of the phys- ical phenomena of spiritualism, the moving of tables, ap])earance of forms, release of the medi- um fi-om knots and bonds, reading of sealed messages, and so on. In this field so much fraud or sleight-of-hand has been discovered that the students in ps^tdiieal research have as a rule recognized the eakness of such evidence. Yet some of the most eminent among them have been unwilling to consider the hypotheses of deception — conscious or unconscious — in certain cases, be- cause of their personal faith in the honesty of the medium ; and in such cases as that of Mrs. Piper, in which the subject in a trance state reveals to sitters knowledge of their private afl'airs appa- rently quite beyond the usual channels of infor- mation, the alternative is presented by the in- vestigators that the information thus revealed is obtained by the cooperation of departed sjiirits, or is suggestive of the action of some such un- known force as telepathy. In many respects the field of psychical re- search and of psychology is the same, though the methods and purpose of the investigators may be distinct. H_vpnotism, subconscious activity, alterations of personality, hysteria, mental auto- matisms, and related topics find recognition in the records of both. A type of such inqiiry is 'ciystal-gazing,' that is, the alleged power to .see in a crystal or other rellccting surface a vis- ual projection of shifting scenes and images, hich upon examination can bo referred to ex- periences subconsciously assimilated. As illus- trations of the e.xereise of the subconscious imag- ination, the record of such instances pos.sesses a distinct value for p.sychology. In the minds of some observers of such plu^nomena they, like other experiences, suggest the working of super- normal mental processes, and cannot in many cases be interpreted upon the psychological prin- ciples just indicated. Equally deserving of men- tion are certain studies, pursued by persons interested in psychical research, that contribute to the psycliology of deception. Such studies have shown how readily the reports of perform- ances purporting to give evidence of supernormal powers are vitiated by the effects of observation, by prejudice, by lack of teclmical knowledge, by lapses of memory and the like. To the credit of psychical research must be jilaced a revival of interest in many worthy ))roblems of ]isycholog>-; the rescue from ob- livion of important illustrative material; the contribution of illuminating aids to the compre- hension of the culture history of the human race; and the social service of setting forth the per- nicious and illusory character of certain systems of belief that threatened at various times the mental health of communities. To its disadvan- tage must be recorded the fostering of what is to some persons an unwholesome interest in the occult. BiBLiOGHAPiiy. The most important publica- tions are those of the English .'-Society for P.sy- ehical Research, of which up to 1!103 seventeen volumes have appeared. In 18S4 there was formed an American Society for Psychical Re- search which published four volumes before it merged its existence with that of the parent society. The best single volume surveying the field is Podmorc's Stiidiex in Psychical Research (London. 1897). Podmore's work on Modern Spiritualism (2 vols., New York, 1002) gives much information upon that as well as kindred topics. Other works worthy of mention in an outline bibliography are .Andrew Lang, Cock-Lane and Common Sense (London, 1894) ; Podmore, Apparitions and Thonfiht Transference (ib.. 1894); Gurney, Myers, and Podmore. Phantasms of the JAvinfi (ili.. 1880) ; !Mason, Telepathi/ and. the Subliminal Self (ib., 1897). In .Jastrow, Fact and. Fable in Psi/chol- ogi/ (1900), will be found a critical survey of certain of the problems and positions of 'p.sy- chical research.' PSYCHICAL RESEARCH, Society for. An association formed in Lonilon, England, early in 1882 (as the result of a conference convoked by Professor W. F. Barrett), for the purpose of making "an organized and systematic attempt to investigate that large group of debatable phe- nomena designntcd bv such terms as mesmeric, psychical, and spiritualistic." Through the aeeney of conmiittees the society has gathered and pub- lished a vast amount of material on the subjects involved, with many discussions thereon. (For a discussion of the results nttnined by the com- mittees, see Psychical Research.) Among the
