The sufferings entailed by this condition are commonplace knowledge, and there is scarcely a novelist who has not dealt with them. It is around matters of sex and of religion that the conflict is most severe, and while it is no part of our purpose to make any detailed survey of the condition, it may be of interest to point out some of the more obvious significances of this localization. Religion has always been to man an intensely serious matter, and when we realize its biological significance we can see that this is due to a deeply ingrained need of his mind. The individual of a gregarious species can never be truly independent and self-sufficient. Natural selection has ensured that as an individual he must have an abiding sense of incompleteness, which, as thought develops in complexity, will come to be more and more abstractly expressed. This is the psychological germ which expresses itself in the religious feelings, in the desire for completion, for mystical union, for incorporation with the infinite, which are all provided for in Christianity and in all the successful sub-varieties of Christianity which modern times have {51} seen develop. This need seems with the increasing complexity of society to become more and more imperious, or rather to be satisfiable only by more and more elaborately rationalized expressions. The following is a representative passage from a recent very popular book of mystical religion: “The great central fact in human life, in your life and in mine, is the coming into a conscious vital realization of our oneness with the Infinite Life and the opening of ourselves fully to this divine inflow.” It is very interestingly shown here to what lengths of rationalization may be forced the consequences of that yearning in us which is identical with the mechanism that binds the wolf to the pack, the sheep to the flock, and to the dog makes the company of his master like walking with God in the cool of the evening. Did an opportunity offer, it would be interesting to inquire into the relation of the same instinctive impulse to the genesis of philosophy. Such an attempt would, however, involve too great a digression from the argument of this essay.