The wisest and noblest teacher is nature itself.

When you look at a wall spotted with stains...you may discover a resemblance to various landscapes, beautiful with mountains, rivers, rocks, trees. Or again, you may see battles and figures in action, or strange faces and costumes, and an endless variety of objects which you could reduce to complete and well-drawn figures.

Experience, the interpreter between creative nature and the human race, teaches the action of nature among mortals: how under the constraint of necessity she cannot act otherwise than as reason, who steers her helm, teaches her to act.

The first object of the painter is to make a flat plane appear as a body in relief and projecting from that plane

The lie is so vile, that even if it were in speaking well of godly things, it would take off something from God's grace; and Truth is so excellent, that if it praises but small things they become noble.

Make your work to be in keeping with your purpose

Common Sense is that which judges the things given to it by other senses.