Just as iron rusts from disuse, and stagnant water putrefies, or when cold turns to ice, so our intellect wastes unless it is kept in use.

Obstacles cannot bend me. Every obstacle yields to effort.

The limiting surface of one thing is the beginning of another.

The painter strives and competes with nature.

We know more about the movement of celestial bodies than about the soil underfoot.

There shall be wings! If the accomplishment be not for me, 'tis for some other. The spirit cannot die; and man, who shall know all and shall have wings.

The Medici made me and the Medici destroyed me.