We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances.

God created everything by number, weight and measure.

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.

I can calculate the motion of heavenly bodies, but not the madness of people.

What the Latins have done in this text (1 John v, 7) the Greeks have done to Paul (1 Tim. iii, 16). They now read, "Great is the mystery of godliness; God manifest in the flesh"; whereas all the churches for the first four or five hundred years, and the authors of all the ancient versions, Jerome as well as the rest, read, "Great is the mystery of godliness, which was manifest in the flesh." Our English version makes it yet a little stronger. It reads, "Great is the mystery of godliness: God was manifest in the flesh."

A cylinder of air reaching to the top of the atmosphere is of equal weight with a cylinder of water about 33 feet high.

All knowledge and understanding of the Universe was no more than playing with stones and shells on the seashore of the vast imponderable ocean of truth.