If I have ever made any valuable discoveries, it has been due more to patient attention, than to any other talent

My powers are ordinary. Only my application brings me success.

That one body may act upon another at a distance through a vacuum, without the mediation of any thing else, by and through which their action and force may be conveyed from one to another, is to me so great an absurdity, that I believe no man, who has in philosophical matters a compentent faculty of thinking, can ever fall into it.

Thus far I have explained the phenomena of the heavens and of our sea by the force of gravity, but I have not yet assigned a cause to gravity. Indeed, this force arises from some cause that penetrates as far as the centers of the sun and planets without any diminution of its power to act, and that acts not in proportion to the quantity of the surfaces of the particles on which it acts (as mechanical causes are wont to do) but in proportion to the quantity of solid matter, and whose action is extended everywhere to immense distances, always decreasing as the squares of the distances.

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

Is not Fire a Body heated so hot as to emit Light copiously? For what else is a red hot Iron than Fire? And what else is a burning Coal than red hot Wood?

Therefore to the same natural effects we must, as far as possible, assign the same causes.