Avicenna

I read the Metaphysics of Aristotle forty times before it made sense to me, and it only made sense because al-Farabi had written a small book explaining its purpose. There is no shame in needing a guide. The shame would be in refusing one.

The soul is the first perfection of a natural organised body that has the potential for life. I read Aristotle's De Anima forty times before I understood it. Then I wrote my own account and found it insufficient. My final position is this: the soul is not identical with the body, and the proof is the Flying Man. Imagine a man created all at once, floating...

The soul is not in the body as a pilot is in a ship, passive and separate, but as a form is in matter — inseparable in life, yet distinct in nature. Remove the body and what remains knows itself still. This is the proof that I call the Flying Man.

Existence is prior to essence in the First Cause alone. All other things receive their existence from without themselves. This distinction — between the Necessary Existent and all contingent beings — is the key that unlocks the door to understanding God without confusing God with the world.

The knowledge of anything, since all things have causes, is not acquired or complete unless it is known by its causes. Medicine considers the human body as to the means by which it may be cured of disease.

The body has its crises; so does knowledge. I completed my first medical work at the age of sixteen. The Canon of Medicine was finished when I was thirty-two and has served as the principal medical text in European and Islamic universities for five centuries since. The Canon is not a collection of observations. It is a system: causes, symptoms, treatments,...

The physician who knows only medicine knows nothing of medicine. Disease arises in bodies that live in climates, hold occupations, eat particular foods, and carry particular griefs. To heal the body, study the whole life.

There are no incurable diseases, only the diseases we have not yet found the treatment for. The physician's despair is premature. Nature works toward restoration always; we must learn to assist rather than obstruct.

Music affects the soul, and the soul affects the body. I have prescribed it. A patient's terror can be dissolved by measured rhythm, and stubborn fevers have been known to break when the mind was calmed by beauty. Do not ask me to justify this only in material terms.

The miniatures that accompany manuscript copies of my Canon of Medicine show a man in robes, reading or writing, surrounded by students. I taught while travelling between courts, often in difficult circumstances. I wrote the Canon partly while riding on horseback, dictating to a student.

The Canon describes the four humours, yes — but also the importance...

The world is divided into men who have wit and no religion, and men who have religion and no wit. My soul is impatient of prison — it has seen the heights and yearns for them still.

Anyone who denies the law of non-contradiction should be beaten and burned until he admits that to be beaten is not the same as not to be beaten, and to be burned is not the same as not to be burned.