perfectly possible to imagine a situation in which murderous thoughts were seething round in a man's mind, but yet in which they never came into contact with that part of his make-up which was concerned with moving his limbs, and generally getting the man himself into action. So you would have a man, thinking the most wicked thoughts within, but calm, placid, and urbane without. In fact however thoughts and actions do always seem to be linked up; so one must ask, “What is the mechanism in the world as we know it which gives motives their compulsive power?”. Obviously physiology and biochemistry play a part; but I find it difficult to believe that this is the whole story.
Curiously enough the best descriptions that I have found of men whose thoughts and actions were dissociated were given by victims of the Nazi Gestapo in describing their inquisitors. Yet if one thinks about it, this is not strange. Where thoughts and actions are dissociated, or nearly so, evil thoughts must go on simmering in the mind endlessly, without any obvious or satisfactory outlet, poisoning the mind, and brooding continually on real or fancied injury. To a lesser degree, there are of course many people in every community intent on acquiring a poker face, or a face which does not betray the normal emotional reactions. This is a kindred phenomenon to complete dissociation of thoughts and action; but is not carried nearly so far. The process of acquiring a poker face has never seemed to me a particularly desirable one.
With the normal person, the process of giving vent to his anger, allows him to “blow off steam”, in colloquial language; even though “blowing off steam” may end the man in greater trouble than before. In other words, expressing one's baser emotions in anger, or violence, or revenge is a form of mental or spiritual relief, at least temporarily; and is a form of relief which for some people apparently is almost a necessity; so much so that consequences are ignored.