PSYCHICAL RESEARCH (from psychic, front Gk. ipexuc6r, pyehikos, relating to the soul or mind, from 1!./VX7,, psyche, breath, life, soul). The term 'psychical research' takes its meaning from the activities of the Society for Psychical Research (q.v.), founded in England in Is82. The original programme of the society proposed a systematic investigation of "that large group of debatable phenomena designated by such terms as mesmeric, psychical, and The work of investigation of these 'residual phenom ena' was intrusted to six committees, who were to inquire severally into "the nature and extent of any influence which may be exerted by one mind upon another apart from any generally recognized mode of perception:" into hypnotism. the so-called mesmeric trance, clairvoyance, and other allied phenomena; to undertake a revision of Reichenbach's researches with reference to discovering whether his possessed "any power of perception beyond a highly exalted sensibility of the recognized sensory organs:" to investigate the reports of apparitions at the moment of death, and of houses reputed to be haunted; to inquire into the causes and general law, of the phenomena of spiritualism; and to collect material relative to the history of these subjects. It becomes apparent that the group of inquiries thus circumscribed does not consti tute a subdivision of an established body of knowledge, but contemplates an extension or revised interpretation of physical and psychical modes of action.
The most extensive investigations of 'psychical research' have been concentrated upon the effort to establish or detect evidence for the transfer ence of thought apart front the recognized chan nels of sense. The experimental evidence has been accumulated by arranging that one person, called the 'agent.' shall think intently of a defi nite mental (usually a visual) impression and attempt to transfer the impression to the mind of the 'percipient.' who is supposed to he en dowed with peculiar powers of this type and who in turn tries to read and record the impres sion thus 'transferred.' Numbers. words. draw ings of simple geometrical forms. sketches of familiar objects, colors. actions, simple calcula tions. or even sounds, tastes, and odors have been 'transferred' in this way. The process of 'trans ference' seems to be more effective when the percipient is in an hypnotic or trance-like condi tion. In such a state there is an increased sensi to slight of sen-e I hyper a.sthesial, which in turn suggests the function ino of an unusual degree of sensibility of the ordinary kind in cases of successful percipiency. The data needed to MAIN the assumption of a non-:sensory mode of thought transference are most difficult to collect: first, because the ex treme delicacy of sensibility in a sensitive nerv ous system is itself responsible for much that passes for thought-transference; secondly, be cause the precautions necessary to eliminate such possibilities have not as a rule been taken ill the seemingly successful experiments, and proper conditions frequently are difficult to se eure; thirdly, because the usual methods of per forming such experiments leave the Avay open for uneon,ciotls exaggeration and misinterpreta tion, as well as for the unconscious indication of hints to the percipient. The experimenters have
taken into account all of these difficulties. Yet, in the opinion of many whose judgment is en titled to great weight, the aveumulated evidence does not justify, even provisionally, the enter tainment of a 'telepathic' hypothesis.
The telepathic hypothesis does not rest its case upon exlicriniental evidence alone. however. It presents an enormously extensive body of wit nesses to the telepathic 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 pro portion of the recorded eases that contain a ver ifiable coincidence of event and presentiment is, on the whole, small. An elaborate census of hallucinations has been gathered by the society, and sets forth the relatively large 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 presentiments may induce the habit of noticing and reeording them. thus in creasing their relative frequency and the oppor tunity for apparently unexplainable coincidence; further by the dominant tend(tney 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 research relate to the asserted manifesta tion of the spirits of the departed hi the affairs of this earth. mainly through individuals known as 'mediums.' Here again the evidence falls into an experimental and an observational group. The experimental evidence is that of the phys ical phenomena of spiritualism, the moving of tables. appearance of forms, release of the medi um from 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 psychical research have as a rule recognized the weakness 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 eases as that of Mrs. Piper, in which the subject in a trance state reveals to sitters knowledge of their private affairs 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 eoiiperation of departed spirits. or is suggestive of the action of some such un blown force as telepathy.