He who immerses himself in sexual intercourse will be assailed by premature aging, his strength will wane, his eyes will weaken, and a bad odour will emit from his mouth and his armpits, his teeth will fall out and many other maladies will afflict him.

While one man can discover a certain thing by himself, another is never able to understand it, even if taught by means of all possible expressions and metaphors, and during a long period; his mind can in no way grasp it, his capacity is insufficient for it.

Every man should view himself as equally balanced: half good and half evil. Likewise, he should see the entire world as half good and half evil.... With a single good deed he will tip the scales for himself, and for the entire world, to the side of good.

The whole object of the Prophets and the Sages was to declare that a limit is set to human reason where it must halt.

Medical practice is not knitting and weaving and the labor of the hands, but it must be inspired with soul and be filled with understanding and equipped with the gift of keen observation . . .

Those who grieve find comfort in weeping and in arousing their sorrow until the body is too tired to bear the inner emotions.

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.