...the real origin and essence of the hypnotic condition, is the induction of a habit of abstraction or mental concentration, in which, as in reverie… - James Braid

In this way, we influence the muscles of physiognomy [facial expression] and it is possible for us to arouse any passion or sentiment whatsoever; the contraction of the interconnected muscles, constituting “the anatomy of expression”, evokes in the brain of the hypnotised person certain impressions just as these, in the waking state, determine the whole facial expression. It is thus merely a reversal of the usual order [of causation] between the emotions and their physical expressions.

We must remember, during a period in history when psychology was still a branch of academic philosophy. The psychological concepts developed by philosophers of mind, such as “dominant ideas” (akin to the automatic thoughts of Beck’s cognitive therapy) “habit and association” (a subjective precursor of Pavlovian conditioning), and “imitation and sympathy” (which we now call “role-modelling” and “empathy”), are as the theoretical framework upon which science of hypnotism, “neuro-hypnology”, was built.

...by the term Hypnotism, or Nervous Sleep, I mean a peculiar condition of the nervous system, into which it may be thrown by artificial contrivance, and which differs, in several respects, from common sleep or the waking condition. I do not allege that this condition is induced through the transmission of a magnetic or occult influence from my body into that of my patients; nor do I profess, by my processes, to produce the higher [i.e., supernatural] phenomena of the Mesmerists. My pretensions are of a much more humble character, and are all consistent with generally admitted principles in physiological and psychological science. Hypnotism might therefore not inaptly be designated, Rational Mesmerism, in contra-distinction to the Transcendental Mesmerism of the Mesmerists.[ Braid, Observations on Trance or Human Hibernation, 1850, 'Preface.