Altruism is a quality the understanding of which has been much obscured by its being regarded from the purely human point of view. Judged from this standpoint, it has been apt to appear as a breach in the supposedly “immutable” laws of “Nature red in tooth and claw,” as a virtue breathed into man from some extra-human source, or as a weakness which must be stamped out of any race which is to be strong, expanding, and masterful. To the biologist these views are equally false, superfluous, and romantic. He is aware that altruism occurs only in a medium specifically protected from the unqualified influence of natural selection, that it is the direct outcome of instinct, and that it is a source of strength because it is a source of union. In recent times, freedom of travel, and the development of the resources rendered available by education, have increased the general mass of intercommunication to an enormous extent. Side by side with this, altruism has come more and more into recognition as a supreme moral law. There is {124} already a strong tendency to accept selfishness as a test of sin, and consideration for others as a test of virtue, and this has influenced even those who by public profession are compelled to maintain that right and wrong are to be defined only in terms of an arbitrary extra-natural code. Throughout the incalculable ages of man’s existence as a social animal, Nature has been hinting to him in less and less ambiguous terms that altruism must become the ultimate sanction of his moral code. Her whispers have never gained more than grudging and reluctant notice from the common man, and from those intensified forms of the common man, his pastors and masters. Only to the alert senses of moral genius has the message been at all intelligible, and when it has been interpreted to the people it has always been received with obloquy and derision, with persecution and martyrdom. Thus, as so often happens in human society, has one manifestation of herd instinct been met and opposed by another.