A Treatise on Painting
by Leonardo da Vinci, translated by John Francis Rigaud
The Method of awakening the Mind to a Variety of Inventions
4007415A Treatise on Painting — The Method of awakening the Mind to a Variety of InventionsJohn Francis RigaudLeonardo da Vinci

Chap. CLXIII.The Method of awakening the Mind to a Variety of Inventions.

I will not omit to introduce among these precepts a new kind of speculative invention, which though apparently trifling, and almost laughable, is nevertheless of great utility in assisting the genius to find variety for composition.

By looking attentively at old and smeared walls, or stones and veined marble of various colours, you may fancy that you see in them several compositions, landscapes, battles, figures in quick motion, strange countenances, and dresses, with an infinity of other objects. By these confused lines the inventive genius is excited to new exertions.