thesis to be spoken of as even possible, in spite of the massive
human tradition based on concrete experience in its favour, has always
seemed to me a curious example of the power of fashion in things
scientific. That the demon theory (not necessarily a devil theory) will
have its innings again is to my mind absolutely certain.... One must be
blind and ignorant indeed to suspect no such possibility...." It must by
no means be taken for granted, therefore, that the intelligences
operating through Mrs. Piper and other mediums are all that they claim
to be, even if their externality to the medium were proved.... We must
be extremely cautious in accepting any messages coming through mediums
until the most certain and convincing proofs of identity be
forthcoming--and _then_ we should be cautious!

The only plausible theory which in any way accounts for the Piper and
similar phenomena--short of the spiritistic--is one based upon the
existence of independently fluctuating strata of the medium's mind,
acquiring their knowledge by means of telepathy, clairvoyance, and other
supernormal means. This view of the case is held and defended with
extreme ingenuity and persuasiveness by Professor Flournoy in his
_Spiritism and Psychology_--a book which I myself think should be read
by every one interested in psychics or inclined to "dabble in
spiritualism." The complete isolation and individuality of the various
personalities involved could only be explained, it seems to me, by
postulating a series of subliminal strata, between which there would be
no memory connection--very much like Mr. Gurney's strata obtained by him
and described in his paper on "The Stages of Hypnotic Memory"
(_Proceedings_, vol. iv. pp. 515-31). In this way alone could we account
for the facts; but even so, are they explained?

When psychical research becomes a recognized science there will be ample
room for "specialization," and for many years of study in each branch of
the work. Consider, for instance, the many ramifications and
possibilities which would be thrown open to the researcher! A man might
become a "specialist" in haunted houses, in the investigation of such
cases, and in their "treatment" and "cure." He would then have to
investigate the nature and character of the phenomena which occur in
them, and of the intelligences which manifest themselves. The nature of
the figures seen in such houses would form a special branch of research,
and the degree of