The natural force within each of us is that greatest healer of all.

The body of man has in itself blood, phlegm, yellow bile and black bile; these make up the nature of this body, and through these he feels pain or enjoys health. Now he enjoys the most perfect health when these elements are duly proportioned to one another in respect of compounding, power and bulk, and when they are perfectly mingled.

Correct is to recognize what diseases are and whence they come; which are long and which are short; which are mortal and which are not; which are in the process of changing into others; which are increasing and which are diminishing; which are major and which are minor; to treat the diseases that can be treated, but to recognize the ones that cannot be, and to know why they cannot be; by treating patients with the former, to give them the benefit of treatment as far as it is possible.

Divine is the task to relieve pain

War is the only proper school of the surgeon.

We must turn to nature itself, to the observations of the body in health and in disease to learn the truth.

Where prayer, amulets and incantations work it is only a manifestation of the patient's belief.