The greatest natural genius cannot subsist on its own stock: he who resolves never to ransack any mind but his own, will be soon reduced, from mere barrenness, to the poorest of all imitations; he will be obliged to imitate himself, and to repeat what he has before often repeated. When we know the subject designed by such men, it will never be difficult to guess what kind of work is to be produced.

Discourse no. 6; vol. 1, p. 158. - Discourses on Art