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. As we have indicated in our comparison, every suggestion which has succeeded leaves a strong trace, or engram, in the brain. It has opened a way by breaking down a barrier or a chasm, and its effect, which appeared hitherto difficult or impossible to realize, will henceforth be much more easy to obtain. This is why considerable cerebral repose is often necessary at first to open a way for a suggestion, while later on its effect can often be obtained even during the agitation of cerebral activity strongly associated with or even led by violent momentary sentiments. The chief characteristic of suggestive action, is that it traverses the paths of subconscious activity, so that its effect occurs unexpectedly in our consciousness.