What connection or what divorce appears to exist between mental and moral qualities in the groups and in the individuals composing them? Are criminals as a rule of a lower order of intelligence than non-criminals? If so, what types of intelligence are associated with different types of crime? For example, do professional burglars and professional confidence men represent different mental types? What are the effects upon these different types of isolation and of mobility, of stimulus and of repression? To what extent can playgrounds and other forms of recreation supply the stimulation which is otherwise sought for in vicious pleasures? To what extent can vocational guidance assist individuals in finding vocations in which they will be able to obtain a free expression of their temperamental qualities? _The moral region._—It is inevitable that individuals who seek the same forms of excitement, whether that excitement be furnished by a horse race or by grand opera, should find themselves from time to time in the same places. The result of this is that in the organization which city life spontaneously assumes the population tends to segregate itself, not merely in accordance with its interests, but in accordance with its tastes or its temperaments. The resulting distribution of the population is likely to be quite different from that brought about by occupational interests or economic conditions. Every neighborhood, under the influences which tend to distribute and segregate city populations, may assume the character of a “moral region.” Such, for example, are the vice districts, which are found in most cities. A moral region is not necessarily a place of abode. It may be a mere rendezvous, a place of resort. In order to understand the forces which in every large city tend to develop these detached milieus in which vagrant and suppressed impulses, passions, and ideals emancipate themselves from the dominant moral order, it is necessary to refer to the fact or theory of latent impulses of men. The fact seems to be that men are brought into the world with all the passions, instincts, and appetites, uncontrolled and undisciplined. Civilization, in the interests of the common welfare, demands the suppression sometimes, and the control always, of these wild, natural dispositions. In the process of imposing its discipline upon the individual, in making over the individual in accordance with the accepted community model, much is suppressed altogether, and much more finds a vicarious expression in forms that are socially valuable, or at least innocuous. It is at this point that sport, play, and art function. They permit the individual to purge himself by means of symbolic expression of these wild and suppressed impulses. This is the catharsis of which Aristotle wrote in his _Poetic_, and which has been given new and more positive significance by the investigations of Sigmund Freud and the psychoanalysts.