We who tic are consumed with a desire for the forbidden fruit. It is when we are required to keep quiet that we are tempted to restlessness; it is when silence is compulsory that we feel we must talk. Now, when one is learning his lessons, conversation is prohibited, the natural consequence being that he seeks to evade the galling interdict by giving vent to some inarticulate sound. In this fashion did my "cluck" come into being. Moreover, we abhor a vacuum, and fill it as we may. Various are the artifices we might employ--such, for instance, as speaking aloud; but that is much too obvious, and does not satisfy: to make a little grunt or cluck, on the other hand--what a comfort in a tic like that! We need not smile at these explanations, for they are corroborated by the facts of clinical observation. Fear of silence is nothing else than a form of phobia, comparable to the fear of open spaces. O.'s account of the origin of his tics supplies further evidence of the mental infantilism of those with whom we are at present concerned. It is the prerogative of "spoilt children" to wish to do exactly what they are forbidden to do. They seem to be animated by a spirit of contrariness and of resistance; and if in normal individuals reason and reflection prevail with the approach of maturity, in these "big babies" many traces of childhood persist, in spite of the march of years. In the strict sense of the words there never has been any echolalia or coprolalia in O.'s case, though it has happened that expressions lacking in refinement have escaped him; but he never has been consciously yet irresistibly urged to utter a gross word. The sole vestige of anything of the kind is a sort of _fruste_ coprolalia that consists in an impulse to use slang--an impulse which he cannot withstand and which he finds consolation in obeying. * * * * * Some additional details may be submitted to illustrate the intimate analogies between tics and obsessions.