O painter skilled in anatomy, beware lest the undue prominence of the bones, sinews and muscles cause you to become a wooden painter from the desire to make your nude figures reveal all.

You will never have a greater or lesser dominion than that over yourself...the height of a man's success is gauged by his self-mastery; the depth of his failure by his self-abandonment. ...And this law is the expression of eternal justice. He who cannot establish dominion over himself will have no dominion over others.

Although human ingenuity may devise various inventions which, by the help of various instruments, answer to one and the same purpose, yet will it never discover any inventions more beautiful, more simple or more practical than those of nature, because in her inventions there is nothing lacking and nothing superfluous; and she makes use of no counterpoise when she constructs the limbs of animals in such a way as to correspond to the motion of their bodies, but she puts into them the soul of the body.

If you put on more clothes as the cold increases, it will have no power to hurt you. Let us hope that.

A bird is an instrument working according to mathematical law, which instrument it is within the capacity of man to reproduce with all its movements.

He who has access to the fountain does not go to the water-pot.

The senses are of the earth, the reason stands apart from them in contemplation.