Maimonides Moving Quotations

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 other-wise than in a straight line, These rectilinear motions of these four elements when returning to their original place are are of two kinds, either centrifugal,vziz.>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.

Galen , in the third section of his book, "The Use of the Limbs," says correctly that it would be in vain to expect to see living beings formed of the blood of menstruous women and the semen virile, who will not die, will never feel pain, or will move perpetually, or shine like the sun. This dictum of Galen is part of the following more general proposition: Whatever is formed of matter receives the most perfect form possible in that species of matter; in each individual case the defects are in accordance with that individual matter.

Whatever form it has, it [matter] will be disposed to receive another form; it never leaves off moving and casting off the form which it has in order to receive another. ...It is therefore clear that all corruption, destruction, or defect comes from matter.