... I have come to believe that any fruitful study of the science of society must rest upon a clear understanding, even though it be but a layman's, of the Darwinian theory. - Keller, Societal Evolution, p. vi.

When new forms of life or society come into existence, another question must be answered before we can say whether or not they spell progress; we must know how selection is made of the variations which are to be preserved and of those which are to be rejected. Mere change is not necessarily progress.