There is no absolute up or down, as Aristotle taught; no absolute position in space; but the position of a body is relative to that of other bodies. Everywhere there is incessant relative change in position throughout the universe, and the observer is always at the center of things.

Nature is none other than God in things. Animals and plants are living effects of Nature; whence all of God is in all things. Think thus, of the sun in the crocus, in the narcissus, in the heliotrope, in the rooster, in the lion.

The stars in the sky are really other suns like our own, around which orbit other planets. (paraphrase)

My son, I do not say these are foals and those asses, these little monkeys and those great baboons, as you would have me do. As I told you from the first, I regard them as earth's heroes. But I do not wish to believe them without cause, nor to accept those propositions whose antitheses (as you must have understood if you are not both blind and deaf) are so compellingly true.

The beginning, middle, and end of the birth, growth, and perfection of whatever we behold is from contraries, by contraries, and to contraries; and whatever contrariety is, there is action and reaction, there is motion, diversity, multitude, and order, there are degrees, succession and vicissitude.

The hammers must be swung in cadence, when more than one is hammering the iron.

There is one basic cause of all effects.