Herbert Spencer

“ There is an ensemble of vital phenomena presented by each organism in the course of its growth, development, and decay; and there is an ensemble of vital phenomena presented by the organic world as a whole. ”

“ What interpretation we put on the facts of structure and function in each living body, depends entirely on our conception of the mode in which living bodies in general have originated. To form some conclusion respecting this mode—a provisional if not a permanent conclusion—must therefore be our first step. ”

“ We have to choose between two hypotheses—the hypothesis of Special Creation and the hypothesis of Evolution. Either the multitudinous kinds of organisms which now exist, and the far more multitudinous kinds which have existed during past geologic eras, have been from time to time separately made ”