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but a form of animal society. Hirnian society is, however, so different from animal society that it is considered by many to be sui generis. But the whole difference between the two, it can readily be shown, is in the forms and definiteness of the psychical interaction between individuals. What especially distinguishes human society from animal groups is the possession of articulate language. It is this which makes possible the communication of definite ideas, giving a far greater degree of definiteness to the whole process of social interaction and making possible among human beings many higher forms of co-operation. Articulate speech, of course, rests in some degree upon the power of form- ing abstract or general ideas, though it in turn reacts to develop that power. Upon these two great differences between man and the other animals — articulate speech and the power of abstract thought — rest the chief differences between animal and human society ; for the other great distinctive marks of human society, such as the rationality and self -consciousness of its individual members, religion, and government, all go back to, or are inti- mately associated with, language and the power of abstract thought.
If what has been said is true, then human society must be regarded as an inheritance from man's prehuman progenitors, and as a form of animal society. Even many of the forms of human association were doubtless fixed in the sub-human stage. This is notably true of man's family life, which in its essential features, as Westermarck and others have shown, must be re- garded as an inheritance from man's apelike progenitors. It is also ti-ue of such a form of association as leader and follower, for the phenomena of leadership are found among many of the higher animals.
In a word, human society rests upon instincts established by natural selection during the long prehuman stage of man's evolu- tion. These instincts were the basis of all the primitive forms of association among men, and the addition to these of the intel- lectual elements of language, abstract ideas, self -consciousness, and reason is what gave rise to the peculiar products of human social evolution, human institutions, and civilization.
