Hypnotism reduced to its simplest principle is, like the old
Fascination, the action of mind upon mind, or of a _mind upon itself_,
in such a manner as to produce a definite belief, action, or result.
It is generally effected by first causing a sleep, as is done in
animal magnetism, during which the subject implicitly obeys the will
of the operator, or performs whatever he suggests. Hence arose the
term Suggestion, implying that what the patient takes into his head to
do, or does, must first be submitted to his own mental action.

Very remarkable results are thus achieved. If the operator, having put
a subject to sleep (which he can do in most cases, if he be clever,
and the experiments are renewed often enough), will say or suggest to
him that on the next day, or the one following, or, in fact, any
determined time, he shall visit a certain friend, or dance a jig, or
wear a given suit of clothes, or the like, he will, when the hypnotic
sleep is over, have forgotten all about it. But when the hour
indicated for his call or dance, or change of garment arrives, he will
be haunted by such an irresistible feeling that he _must_ do it; that
in most cases it will infallibly be done. It is no exaggeration to say
that this has been experimented on, tested and tried thousands of
times with success and incredible ingenuity in all kinds of forms and
devices. It would seem as if spontaneous attention went to sleep, but,
like an alarm clock, awoke at the fixed hour, and then _reflex_
action.

Again--and this constitutes the chief subject of all I here discuss--
we can _suggest_ to ourselves so as to produce the same results. It
seems to be a curious law of Nature that if we put an image or idea
into our minds with the preconceived determination or intent that it
shall recur or return at a certain time, or in a certain way, after