At a time when the activity of the brain was not understood, the existence of an essential mind and a free will were assumed, independent of the law of the conservation of energy and of the law of causality, independent therefore of the brain, the activity of which they commanded more or less at their pleasure. This conception is based on ignorance of the facts.
Let us return to our example: why does the idea of my wife call to mind that of the journey? It might quite as well suggest others. In reality, a number of ideas, or subconscious cerebral activities, act at the same time as that of my wife to give rise to the idea of the journey. This journey had already been decided on before thinking of it at the moment in question, and the resolution that I had taken to make it had left in my brain latent impressions (engrams) which slumbered there; such as those of the date of departure, the duration of the journey, its termination, precautions to be taken for the house during our absence, things to take with us, expenses, etc., etc. During the infinitely short time when the idea of journey appears in my consciousness, between that of my wife and that of my trunk, I have no consciousness of all these things. They are, however, closely associated with the idea of journey, and in connection with it by the thousand threads of a subconscious and latent cerebral force which takes place in my cerebral nerve-elements (neurones); and it is their hidden action which awakens the idea of journey and directs my attention to it, at the same time weakening by their divers interferences the intensity of other associated engrams; in particular that of the sentiment of traveling, and thereby preventing a series of ideo-motor sensations relating to departure from becoming predominant.
What suddenly appears in my consciousness is the verbal representation symbolized by the word journey; a general representation of synthetic nature, and consequently nebulous. It is the words of language only which allow me to synthetize a general idea in a short and definite form. Thus, the cerebral flash journey which follows the idea of my wife is not caused by the latter idea alone; it has been mainly drawn from its obscurity and brought before the mobile conscious attention, by the action of the thousand subconscious threads, some of which we have just mentioned, and which have at the same time determined its quality.
Without my being aware of it, these dynamic threads, or latent engrams, have to a great extent determined the kind of idea which will follow that of journey, and which will seem to me to be caused by this last alone, namely the idea of trunk. The idea of journey might equally well have awakened other images, such as those of the acquaintances whom I should meet, or of the town I intended to visit. Why that of the trunk? This is simply because the care of the effects to be taken, the place they should occupy, etc., revolved unconsciously but strongly in my brain, and for the moment predominated over other subconscious associations.
This simple example shows us that in reality the three successive ideas, wife, journey, trunk, are more under the influence of sentiments, representations and former volitions in a latent and subconscious state, than dependent on each other. But these latter activities are themselves the product of other antecedent activities of my brain, extraordinarily diverse and complex. I will attempt to make things a little more complete and comprehensible by the aid of a comparison.
A man finds himself in the middle of a compact and moving crowd. He cries out to attract the attention of the crowd. His voice is heard by those immediately around him, but is lost on the moving mass. Against his will he is carried away by the crowd in the direction of the strongest movement. But if the crowd is immobile and tranquil the same man may make himself heard, and may even force his way through the crowd and impel it in his turn by the impression that his words have made on it.
Something analogous to this occurs in the action of an idea according as it is produced in a brain which is awake, active and strongly associated, or on the contrary in a brain which rests and sleeps. The brain which is active and strongly associated resembles the agitated crowd which carries away everything by its activity. In this case a single idea, like a single man, cries out in vain, i.e., is produced strongly; it will not impel, but will be carried away or stifled, unless it already possesses, by the former remembrances (engrams) which it may revive, a particular power over the brain. It is the same with the agitated crowd; if the man who cries out is already known and has influence and power, he may arrest it and even bring it toward the center of his agitation. The brain which is at rest or sleeping, i.e., feebly associated and not active, resembles the immobile crowd. Even when it is new and has not yet become fixed in the memory, an idea may produce a deep impression, and awaken activities in its own direction. I repeat, if this idea has already acted more or less powerfully on the cerebral activity that it has often carried with it, it has accustomed this to follow it (i.e., fortified the engrams and facilitated their ecphoria), and then the powerful associated engrams which it has left in the organ of thought, will often be capable of carrying everything with them, even to the center of the agitation.
In this way I succeeded in suddenly calming by hypnotism a woman who was mad with despair over the tragic death of half her family in a fire, by the simple fact that I had often hypnotized her previously. Immediately after the hypnosis she went away quietly to the place of the disaster and was the only one to keep her presence of mind and put things in order.
I refer the reader to what has been said concerning the mneme (Chapter I). Semon's theory throws light on these questions.
The first thing necessary for suggestion or hypnotism is to put the brain of the subject in a state of relative repose, so as to prepare a soil ready to receive suggestions. These are then made so as to always increase the cerebral repose, in order to weaken the action of the threads of subconscious association of which we have spoken above. Lastly, the suggestion (or idea which symbolizes the effect it is desired to obtain) is accentuated as much as possible, and in a form which at once excludes all contradiction. For this purpose everything should be utilized—sentiments and associations which are easily introduced, agreeable or repulsive sensations, volitions, etc. Nothing paralyzes a suggestive effect so much as emotions, violent sentiments in general, inclinations, or repulsions which act in the opposite direction, whether they arise from fear, despair, hatred, sadness, joy, love or any kind of affective conditions. The same brain, accessible to all kinds of suggestions, will repress some of them as soon as it feels a deep sympathy for their contrary. We may suggest in vain to an amorous woman, the hatred or disgust of her lover, for the sentiment of love is stronger than the effect of a strange suggestion, and every suggestion which opposes the strongest aspirations of sentiment provokes mistrust and repulsion, which in their turn destroy all suggestive power.