Study without desire spoils the memory, and it retains nothing that it takes in.

Let proportion be found not only in numbers and measures, but also in sounds, weights, times, and positions, and what ever force there is.

The motions of men must be such as suggest their dignity or their baseness.

The painter strives and competes with nature.

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

After painting comes Sculpture, a very noble art, but one that does not in the execution require the same supreme ingenuity as the art of painting, since in two most important and difficult particulars, in foreshortening and in light and shade, for which the painter has to invent a process, sculpture is helped by nature. Moreover, Sculpture does not imitate color which the painter takes pains to attune so that the shadows accompany the lights.

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.