Commune with your own heart upon your bed, and be still.

For the elements have the property of moving back to their place in a straight line, but they have no properties which would cause them to remain where they are, or to move otherwise than in a straight line. The rectilinear motions of these four elements when returning to their original place are of two kinds, either centrifugal, viz., the motion of the air and the fire; or centripedal, viz., the motion of the earth, and the water; and when the elements have reached their original place, they remain at rest.

It is well known among physicians that the best of the nourishing foods is the one that the Moslem religion forbids, i.e., Wine. It contains much good and light nourishment. It is rapidly digested and helps to digest other foods.

Do not imagine that these most difficult problems can be thoroughly understood by any one of us.

Lose with truth and right rather than gain with falsehood and wrong.

The people who are abroad are all those that have no religion, neither one based on speculation nor one received by tradition. Such are the extreme Turks that wander about in the north, the Kushites who live in the south, and those in our country who are like these. I consider these as irrational beings, and not as human beings; they are below mankind, but above monkeys, since they have the form and shape of man, and a mental faculty above that of the monkey.

It is thus necessary to examine all things according to their essence, to infer from every species such true and well established propositions as may assist us in the solution of metaphysical problems.