From this view came the belief that man as existing is degenerate. This degeneracy, while popularly charged to occult influences, was early ascribed by scientists to physical causes. Aristotle, as Osborn[4] points out, appears to have recognised degeneration or the gradual decline of structures in form and usefulness, in his analysis of "movement" in connection with development. Degeneration is first met with as a term in an explanation of the origin of species by Buffon in the eighteenth century. The conception itself occurs in a criticism by Sylvius of Vesalius (1514-64), who had asserted that the anatomy of Galen could not have been founded upon the human body, because he had described an intermaxillary bone. This bone, Vesalius observed, is found in the lower animals but not in man. Sylvius (1614-72) defends Galen on the ground that though man had no intermaxillary bone at present this is no proof of its absence in Galen's time. "It is luxury, it is sensuality, which has gradually deprived man of this bone." This passage, as Osborn remarks, proves that the idea of degeneration of structures through disuse, as well as the idea of the inheritance of the effect of habit, or the "transmission of acquired characters," is a very ancient one. Sylvius, while here recognising factors of degeneracy, erred in considering disappearance of the intermaxillary bone, not reappearance, as degeneracy. He failed to recognise, moreover, the law of economy of growth by which one structure is sacrificed for another or for the organism as a whole. This law, indicated by Aristotle, but clearly outlined by Goethe in 1807, and Geoffroy St. Hilaire in 1818, underlies the physiological atrophies and hypertrophies which play such a part in degeneracy. The _Twelve Cæsars_ of Suetonius (that stud book of imperial degeneracy as it has been styled) stamps the decided impression on its readers that Hippocratian notions of degenerate heredity strongly permeated Roman thought, to revive in those Arabic, Italian, and British (Roger Bacon) thinkers who created the scientific phase of the revival of learning. In the science of medicine, as developed by Hippocrates,[5] the modern conception of degeneracy is evident. Hippocrates argues against the "sacred" nature of epilepsy, since it is a hereditary disease and hence comes under the operation of physical law. He furthermore points out, as did Aristotle, that epilepsy produced in the ancestor by traumatism and other physical causes may be inherited by the child.