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.

There is no difference between the pain of humans and the pain of other living beings, since the love and tenderness of the mother for the young are not produced by reasoning, but by feeling, and this faculty exists not only in humans but in most living beings.

Do not imagine that what we have said of the insufficiency of our understanding and of its limited extent is an assertion founded only on the Bible: for philosophers likewise assert the same, and perfectly understand it,- without having regard to any religion or opinion.

To sum up: I am the man who when the concern pressed him and his way was straitened and he could find no other device by which to teach a demonstrable truth other than by giving satisfaction to a single virtuous man while displeasing ten thousand ignoramuses - I am he who prefers to address that single man by himself, and I do not heed the blame of those many creatures.

You will certainly not doubt the necessity of studying astronomy and physics, if you are desirous of comprehending the relation between the world and Providence as it is in reality, and not according to imagination.

All this is applicable to the intellectual faculties of man. There is a considerable difference between one person and another as regards these faculties, as is well known to philosophers.

Truth does not become more true by virtue of the fact that the entire world agrees with it, nor less so even if the whole world disagrees with it.