Germany the Newtonian fallacies still have undisturbed possession of the professorial chair, and men continue to speak quite seriously of the seven homogeneous rays of light and their different refrangibility, will some day be numbered among the great intellectual peculiarities of men generally, and especially of Germans. From the same cause as we have referred to above, may be explained the equally well-known fact that, conversely, admirable mathematicians have very little susceptibility for works of fine art. This is very naïvely expressed in the well-known anecdote of the French mathematician, who, after having read Racine’s “Iphigenia,” shrugged his shoulders and asked, “_Qu’est ce que cela prouve?_” Further, as quick comprehension of relations in accordance with the laws of causality and motivation is what specially constitutes prudence or sagacity, a prudent man, so far as and while he is so, will not be a genius, and a man of genius, so far as and while he is so, will not be a prudent man. Lastly, perceptive knowledge generally, in the province of which the Idea always lies, is directly opposed to rational or abstract knowledge, which is guided by the principle of the ground of knowing. It is also well known that we seldom find great genius united with pre-eminent reasonableness; on the contrary, persons of genius are often subject to violent emotions and irrational passions. But the ground of this is not weakness of reason, but partly unwonted energy of that whole phenomenon of will—the man of genius—which expresses itself through the violence of all his acts of will, and partly preponderance of the knowledge of perception through the senses and understanding over abstract knowledge, producing a decided tendency to the perceptible, the exceedingly lively impressions of which so far outshine colourless concepts, that they take their place in the guidance of action, which consequently becomes irrational. Accordingly the impression of the present moment is very strong with such persons, and carries them away into unconsidered action, violent emotions and passions. Moreover, since, in general, the knowledge of persons of genius has to some extent freed itself from the service of will, they will not in conversation think so much of the person they are addressing as of the thing they are speaking about, which is vividly present to them; and therefore they are likely to judge or narrate things too objectively for their own interests; they will not pass over in silence what would more prudently be concealed, and so forth. Finally, they are given to soliloquising, and in general may exhibit certain weaknesses which are actually akin to madness. It has often been remarked that there is a side at which genius and madness touch, and even pass over into each other, and indeed poetical inspiration has been called a kind of madness: _amabilis insania_, Horace calls it (Od. iii. 4), and Wieland in the introduction to “Oberon” speaks of it as