Talent works for money and fame; the motive which moves genius to productivity is, on the other hand, less easy to determine. It isn't money, for genius seldom gets any. It isn't fame: fame is too uncertain and, more closely considered, of too little worth. Nor is it strictly for its own pleasure, for the great exertion involved almost outweighs the pleasure. It is rather an instinct of a unique sort by virtue of which the individual possessed of genius is impelled to express what he has seen and felt in enduring works without being conscious of any further motivation. It takes place, by and large, with the same sort of necessity as a tree brings forth fruit, and demands of the world no more than a soil on which the individual can flourish.

Vol. 2 "On Philosophy and the Intellect" as translated in Essays and Aphorisms (1970), as translated by R. J. Hollingdale - Parerga and Paralipomena (1851) - Counsels and Maxims