So far, we have regarded the gregarious animal objectively. We have seen that he behaves as if the herd were the only environment in which he can live, that he is especially sensitive to impulses coming from the herd, and quite differently affected by the behaviour of animals not in the herd. Let us now try to estimate the mental aspects of these impulses. Suppose a species in possession of precisely the instinctive endowments which we have been considering, to be also self-conscious, and let us ask what will be the forms under which these phenomena will present themselves in its mind. In the first place, it is quite evident that impulses derived from herd feeling will enter the mind with the value of instincts—they will present themselves as “_a priori_ syntheses of the most perfect sort needing no proof but their own evidence.” They will not, however, it is important to remember, necessarily always give this quality to the same specific acts, but will show this great distinguishing characteristic that they may give to _any opinion whatever_ the characters of instinctive belief, making it into an “_a priori synthesis_”; so that we shall expect to find acts which it would be absurd to look upon as the results of specific instincts carried out with all the enthusiasm of instinct, and displaying {31} all the marks of instinctive behaviour. The failure to recognize this appearance of herd impulse as a tendency, as a power which can confer instinctive sanctions on any part of the field of belief or action, has prevented the social habit of man from attracting as much of the attention of psychologists as it might profitably have done. In interpreting into mental terms the consequences of gregariousness, we may conveniently begin with the simplest. The conscious individual will feel an unanalysable primary sense of comfort in the actual presence of his fellows, and a similar sense of discomfort in their absence. It will be obvious truth to him that it is not good for the man to be alone. Loneliness will be a real terror, insurmountable by reason. Again, certain conditions will become secondarily associated with presence with, or absence from, the herd. For example, take the sensations of heat and cold. The latter is prevented in gregarious animals by close crowding, and experienced in the reverse condition; hence it comes to be connected in the mind with separation, and so acquires altogether unreasonable associations of harmfulness. Similarly, the sensation of warmth is associated with feelings of the secure and salutary. It has taken medicine many thousands of years to begin to doubt the validity of the popular conception of the harmfulness of cold; yet to the psychologist such a doubt is immediately obvious.[M]