specifically by instinctive reactions. We see also fragments of instinctive reactions and primitive feeling woven into the total states of social consciousness. The hunger motive may, and probably does, supply some of the elements of the fear and the aggressive moods of war; just as the sex motive provides some of the elements of anger and hatred, and some of the qualities of combat itself. _The Aggressive Instinct_ A natural, but somewhat naive explanation of war is that it is a survival of the aggressive instinct that man has brought up with him from animal life, in which he originated, and that very early in his career was directed toward his fellow men. This aggressive instinct as expressed in the modern spirit of war does not need, on this view, to be thought of as something reverted to. It is still active throughout the social life. Both the purposes and the methods of it remain. We have referred to one aspect of this before, and to the objection that can be made that the ancestry of man does not show us such an aggressive instinct. The nearest relatives of man are mainly social rather than aggressive in their habits. Even the habits of hunting other animals and eating animal food appear to have been acquired during man's career as man, and he never has had the aggressive temper that some creatures have had. Man has acquired a very effectual and very complex adjustment to his environment by piecing together, so to speak, fragments of his original conduct, and developing mechanisms that have been produced in the race as a means of satisfying fundamental needs. Modes of reaction produced originally for one purpose have apparently been utilized by other motives. Of course the more specific animal instincts are not wholly lacking, but it is also true that man through his social life has produced habits that resemble or are substitutes for primitive instincts. The love of combat, especially as it is shown in play indicates the presence of instinctive roots, but it does not show the existence of a definite instinct of aggression. This play is in part an off-shoot of the reproductive motive. These fighting plays of children are in part sexual plays, and we see them clearly in their true light in some of the higher mammals most closely related to man.