Disease is an abnormal state of the body which primarily and independently produces a disturbance in the normal functions of the body. It may be an abnormality of temperament or form (structure). Symptom is a manifestation of some abnormal state in the body. It may be harmful as a colic pain or harmless as the flushing of cheeks in peripneumonia.

Width of life is more important than length of life.

Pure earth does not petrify, because the predominance of dryness over [i.e. in] the earth endows it not with coherence but rather with crumbliness. In general, stone is formed in two ways only (a) through the hardening of clay, and (b) by the congelation [of waters].

That whose existence is necessary must necessarily be one essence.

An ignorant doctor is the aide-de-camp of death.

There are no incurable diseases — only the lack of will. There are no worthless herbs — only the lack of knowledge.

The physical signs of measles are nearly the same as those of smallpox, but nausea and inflammation is more severe, though the pains in the back are less.