Every body persists in a state of rest or of uniform motion in a straight line, unless it is compelled to change that state by forces having impact upon it.

The best and safest way of philosophising seems to be, first to enquire diligently into the properties of things, and to establish those properties by experiences [experiments] and then to proceed slowly to hypotheses for the explanation of them. For hypotheses should be employed only in explaining the properties of things, but not assumed in determining them; unless so far as they may furnish experiments.

When two forces unite, their efficiency double.

I see I have made myself a slave to Philosophy, but if I get free of Mr. Linus's business I will resolutely bid adew to it eternally, excepting for what I do for my private satisfaction or leave to come out after me. For I see a man must either resolve to put out nothing new or to become a slave to defend it.

When the adversaries of Erasmus had got the Trinity into his edition, they threw by their manuscript as an old almanac out of date.

The description of right lines and circles, upon which geometry is founded, belongs to mechanics. Geometry does not teach us to draw these lines, but requires them to be drawn.

No sciences are better attested than the religion of the Bible.