Drawing is based upon perspective, which is nothing else than a thorough knowledge of the function of the eye.

I wish to work miracles.

But to me all sciences seem vain and full of error that are not born of experience, mother of all certainty, and do not terminate in an actual experience.

The first of all simple colours is White ... We shall set down White for the representative of light, without which no colour can be seen; Yellow for the earth; Green for water; Blue for air; Red for fire; and Black for total darkness.

That which can be lost cannot be deemed riches.

As every divided kingdom falls, so every mind divided between many studies confounds and saps itself.

We, by our arts may be called the grandsons of God.