I am never weary of being useful... In serving others I cannot do enough. No labor is sufficient to tire me.

The art of procreation and the members employed therein are so repulsive, that if it were not for the beauty of the faces and the adornments of the actors and the pent-up impulse, nature would lose the human species.

Perspective is the rein and rudder of painting.

In whatever system where the weight attached to the wheel should be the cause of motion of the wheel, without any doubt the center of the gravity of the weight will stop beneath the center of its axle. No instrument devised by human ingenuity, which turns with its wheel, can remedy this effect. Oh, speculators about perpetual motion, how many vain chimeras have you created in the like quest. Go and take you place with the seekers after gold.

The painter's mind is a copy of the divine mind, since it operates freely in creating the many kinds of animals, plants, fruits, landscapes, countrysides, ruins, and awe-inspiring places.

The truth of things is the chief nutriment of superior intellects.

Make your work to be in keeping with your purpose