It is in the nature of water ... to become transformed into earth through a predominating earthy virtue; ... it is in the nature of earth to become transformed into water through a predominating aqueous virtue.

The world is divided into men who have wit and no religion and men who have religion and no wit.

The different sorts of madness are innumerable.

Medicine deals with the states of health and disease in the human body. It is a truism of philosophy that a complete knowledge of a thing can only be obtained by elucidating its causes and antecedents, provided, of course, such causes exist. In medicine it is, therefore, necessary that causes of both health and disease should be determined.

Those who deny the first principle should be flogged or burned until they admit that it is not the same thing to be burned and not burned, or whipped and not whipped.

In God alone, essence (what He is) and existence (that he is) coincide.

Leeches should be kept a day before applying them. They should be squeezed to make them eject the contents of their stomachs.