All that produces a strong excitation, all that modifies the preliminary state of the thoughts and the feelings, surely also modifies the mental and … - James Braid

Strictly speaking, the word hypnotism should be reserved only for those patients who actually fall into a state of sleep, and who forget upon awakening all that occurred during this state. When this is lacking, it is a question merely of reverie or dreaming. It would therefore be apposite to establish a terminology, characterising these modifications which result from the hypnotic process; indeed, with regard to those conditions resistant to ordinary medication and suitable for cure by hypnotism, hardly one patient in ten arrives at the unconscious stage of sleep (at least for the whole duration of the process). The word “hypnotism” can then lead them into error and make them believe that they do not benefit in any way from a process of which the characteristic and obvious effects do not appear to be those that the name [i.e., "hypnotic sleep"] indicates.

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.