Page:Popular Science Monthly Volume 31.djvu/526

510 from barrow and picture-writing, with singular ingenuity. Anthropology and sociology have acquired the rank of distinct sciences. The study of institutions has reached a sudden development under the hands of Spencer, Tylor, McLennan, Maine, Freeman, Lang, and Bagehot. Comparative mythology and folk-lore have asserted their right to a full hearing. Evolutionism has penetrated all the studies which bear upon the divisions of human life. Language, ethnography, history, law, ethics, and politics, have all felt the widening wave of its influence. The idea of development and affiliation has been applied to speech, to writing, to arts, to literature, nay, even to such a detail as numismatics. Our entire view of man and his nature has been reversed, and a totally fresh meaning has been given to the study of savage manners, arts, and ideas, as well as to the results of antiquarian and archaeological inquiry.

In psychology, the evolutionary impulse has mainly manifested itself in Herbert Spencer, and to a less degree in Bain, Sully, Romanes, Croom Robertson, and others of their school. The development of mind in man and animal has been traced pari passu with the development of the material organism. Instinct has been clearly separated from reason: the working of intelligence and of moral feeling has been recognized in horse and dog, in elephant and parrot, in bee and ant, in snail and spider. The genesis and differentiation of nervous systems have been fully worked out. Here Maudsley has carried the practical implications of the new psychology into the domain of mental pathology, and Ferrier has thrown a first ray of light upon the specific functions of portions of the brain. Galton's "Hereditary Genius" and other works have also profoundly influenced the thought of the epoch: while Bastian, Clifford, Jevons, and others have carried the same impulse with marked success into allied lines of psychological research.

But the evolutionary movement as a whole sums itself up most fully of all in the person and writings of Herbert Spencer, whose active life almost exactly covers and coincides with our half-century. It is to him that we owe the word evolution itself, and the general concept of evolution as a single, all-pervading natural process. He, too, has traced it out alone through all its modes, from sun and star, to plant and animal and human product. In his "First Principles," he has developed the system in its widest and most abstract general aspects; in the "Principles of Biology," he has applied it to organic life; in the "Principles of Psychology," to mind and habit; in the "Principles of Sociology," to societies, to politics, to religion, and to human activities and products generally. In Spencer, evolutionism finds its personal avatar: he has been at once its prophet, its priest, its architect, and its builder.

Second only in importance to the evolutionary movement among the scientific advances of our own day must be reckoned the