The seed of a tree has the nature of a branch or twig or bud. It is a part of the tree, but if separated and set in the earth to be better nourished, the embryo or young tree contained in it takes root and grows into a new tree.

Our present work sets forth mathematical principles of philosophy. For the basic problem of philosophy seems to be to discover the forces of nature from the phenomena of motions and then to demonstrate the other phenomena from these forces. It is to these ends that the general propositions in books 1 and 2 are directed, while in book 3 our explanation of the system of the world illustrates these propositions.

Nature does nothing in vain when less will serve; for Nature is pleased with simplicity and affects not the pomp of superfluous causes.

He who thinks half-heartedly will not believe in God; but he who really thinks has to believe in God.

All my discoveries have been made in answer to prayer.

The degree and duration of the torment of these degenerate and anti-Christian people, should be no other than would be approved of by those angels who had ever labored for their salvation, and that Lamb who had redeemed them with his most precious blood.

If you are affronted it is better to pass it by in silence, or with a jest, though with some dishonor, than to endeavor revenge. If you can keep reason above passion, that and watchfulness will be your best defenders.