AVICENNA

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

As to the mental essence, we find it in infants devoid of every mental form.

The knowledge of anything, since all things have causes, is not acquired or complete unless it is known by its causes.

Now it is established in the sciences that no knowledge is acquired save through the study of its causes and beginnings, if it has had causes and beginnings; nor completed except by knowledge of its accidents and accompanying essentials.

That whose existence is necessary must necessarily be one essence.

Therefore in medicine we ought to know the causes of sickness and health.

One learns the states of the human body with respect to what is healthy and what deviates from it, for the purpose of preserving health when it already exists and restoring it when it has been lost.

In medicine it is … necessary that causes both health and disease should be determined.

Pain is a sensation produced by something contrary to the course of nature and this sensation is set up by one of two circumstances: either a very sudden change of the temperament (or the bad effect of a contrary temperament) or a solution of continuity.

Medicine is the science by which we learn the various states of the human body in health and when not in health, and the means by which health is likely to be lost and, when lost, is likely to be restored back to health. In other words, it is the art whereby health is conserved and the art whereby it is restored after being lost. While some divide medicine into a theoretical and a practical [applied] science, others may assume that it is only theoretical because they see it as a pure science. But, in truth, every science has both a theoretical and a practical side.

A horse is simply a horse.

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.

I [prefer] a short life with width to a narrow one with length.

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.

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.

The more brilliant the lightning, the quicker it disappears.

God, the supreme being, is neither circumscribed by space, nor touched by time; he cannot be found in a particular direction, and his essence cannot change. The secret conversation is thus entirely spiritual; it is a direct encounter between God and the soul, abstracted from all material constraints.

Width of life is more important than length of life.

Medicine considers the human body as to the means by which it is cured and by which it is driven away from health.

The different sorts of madness are innumerable.

Prayer is that which enables the soul to realize its divinity. Through prayer human beings worship absolute truth, and seek an eternal reward. Prayer is the foundation-stone of religion; and religion is the means by which the soul is purified of all that pollutes it. Prayer is the worship of the first cause of all things, the supreme ruler of all the world, the source of all strength. Prayer is the adoration of the one whose being is necessary.

But the fact is that when wine is taken in moderation, it gives rise to a large amount of breath, whose character is balanced, and whose luminosity is strong and brilliant. Hence wine disposes greatly to gladness, and the person is subject to quite trivial exciting agents. The breath now takes up the impression of agents belonging to the present time more easily than it does those which relate to the future; it responds to agents conducive to delight rather than those conducive to a sense of beauty.

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.

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

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