h it is naturally impossible for me in this place to give
you any account of the evidence on which the admission of such a
consciousness is based. You will find it set forth in many recent
books, Binet's Alterations of Personality[123] being perhaps as good a
one as any to recommend.

[123] Published in the International Scientific Series.

The human material on which the demonstration has been made has so far
been rather limited and, in part at least, eccentric, consisting of
unusually suggestible hypnotic subjects, and of hysteric patients. Yet
the elementary mechanisms of our life are presumably so uniform that
what is shown to be true in a marked degree of some persons is probably
true in some degree of all, and may in a few be true in an
extraordinarily high degree.

The most important consequence of having a strongly developed
ultra-marginal life of this sort is that one's ordinary fields of
consciousness are liable to incursions from it of which the subject
does not guess the source, and which, therefore, take for him the form
of unaccountable impulses to act, or inhibitions of action, of
obsessive ideas, or even of hallucinations of sight or hearing. The
impulses may take the direction of automatic speech or writing, the
meaning of which the subject himself may not understand even while he
utters it; and generalizing this phenomenon, Mr. Myers has given the
name of automatism, sensory or motor, emotional or intellectual, to
this whole sphere of effects, due to "up-rushes" into the ordinary
consciousness of energies originating in the subliminal parts of the
mind.

The simplest instance of an automatism is the phenomenon of
post-hypnotic suggestion, so-called. You give to a hypnotized subject,
adequately susceptible, an order to perform some designated act--usual
or eccentric, it makes no difference-- after he wakes from his hypnotic
sleep. Punctually, when the signal comes or the time elapses upon which
you have told him that the act must ensue, he performs it;--but in so
doing he has no recollection of your suggestion, and he always trumps
up an improvised pretext for his behavior if the act be of an eccentric
kind. It may even be suggested to a subject to have a vision or to
hear a voice at a certain interval after waking, and when the time
comes the vision is seen or the voice heard, with no inkling on the
subject's part of its source.

In the wonderful explorations by Binet, Janet, Breuer, Fre