Goethe’s discovery of the intermaxillary bone in a human jaw finally disposed of the notion that it is possible to draw a sharp line of distinction between the physical nature of man and that of other vertebrates. And it led Goethe to the theory that all organic beings of the same class are formed in accordance with ideal types or patterns, which Nature modifies indefinitely to suit varying conditions. This conception marked an epoch in the history of scientific thought, for by fastening attention on the fact that organic beings of the same class, however widely their organs may seem to differ from one another, have a fundamental agreement in structure, it directly prepared the way for the discovery of the law of evolution, in which this fact is taken up and explained. It was impossible for Goethe, while occupied so much with science and public affairs, to devote his best energies to imaginative creation. He did not, however, wholly neglect literature. In 1776 he planned a great prose drama, “Iphigenie,” and in 1779 it was written to his dictation. The play was represented with brilliant success at the Weimar Court, Corona Schröter taking the part of the heroine, and Goethe himself that of Orestes. It is wholly different, both in conception and execution, from his earlier dramas. It contains no violent outbursts of passionate feeling; the diction is measured and dignified; and the utmost pains are taken to secure that the various parts shall each have the place that properly belongs to them in the general scheme. It has often been said that the change in Goethe’s method, from the frank, glowing style of the works by which he established his fame, to the consciously artistic style of his mature writings, was wholly due to the impressions derived during his visit to Italy. In reality, as the prose “Iphigenie” shows, it began long before he went to Italy; and no doubt we must to some extent associate it with the change which passed over his character as a whole. Goethe’s aim was, above all things, to master himself, to have every element of his nature under control; and it was inevitable that the strenuous efforts he made to attain this object should leave their mark on his art as well as on his practical life.