Be convinced that, if man were able to reach the end without preparatory studies, such studies would not be preparatory but tiresome and utterly superfluous.

Man's obsession to add to his wealth and honor is the chief source of his misery.

I will destroy my enemies by converting them to friends.

Astrology is a disease, not a science... It is a tree under the shadow of which all sorts of superstitions thrive. ... Only fools and charlatans lend value to it.

Truth does not become more true by virtue of the fact that the entire world agrees with it, nor less so even if the whole world disagrees with it.

Medical practice is not knitting and weaving and the labor of the hands, but it must be inspired with soul and be filled with understanding and equipped with the gift of keen observation . . .

The goal of good health is to enable a person to acquire wisdom.