The main root of group antipathy is in all probability fear. Hatred is an aspect of the aggressive defensive toward the stranger. Hatred is a part of the aggressive reaction. As an expression of ferocity toward all who are not known to be friendly, it belongs to the first line of defense. Hatred is likely to be strong in the female because the attitude of the female is universally defensive. In the beginning, as MacCurdy (37) says, the contrasts between groups were sharp, and these definitely separated groups must have felt toward one another not only antagonism but a sense of being different in kind. Intensity of feelings of opposition tends to magnify small differences into specific differences. This sense of specific difference is never lost, not even in the consciousness of enlightened nations in regard to one another, and we may see it to-day displayed as a mystic belief, on the part of many peoples, in their own superiority. Nations are always outsiders to one another, and the sense of strangeness perennially sustains defensive attitudes and moods of hatred. The friendship of nations can never be very secure, because the old idea of difference of kind is never quite abandoned. Some degree of enmity seems always to be felt toward the foreigner; that is, toward all who are not interested in the protective functions of the group. MacCurdy thinks the intensity of suspicion and hatred of peoples toward one another belongs to the pathological field, and that one expression of this is the peculiarity of the mental processes by which nations always justify their own cause in war. This, however, is perhaps an exaggeration, since we can trace these states of mind in all the history of the race. How deep-seated the enmities and the sense of strangeness among nations may be is seen in the fact that national groups living in close proximity to one another tend to become less friendly rather than to become affiliated. These feelings gradually produce conceptual entities, which stand for the reality of the foreign. These concepts are deposits, so to speak, from a great number of affective reactions, and they always contain imaginative content based upon enmity and suspicion. This underlying enmity between neighboring peoples is not something rare in the world. All foreigners, even in the minds of the most intelligent of peoples, are reconstructions, caricatures. These feelings and attitudes are strong and deep and they prevent genuine friendship among nations. We tend to think of all foreigners as in some degree malicious, as designing, and lacking in the good qualities and right habits which we ourselves possess.