Isaac Newton

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.

Plato is my friend, Aristotle is my friend, but my greatest friend is truth.

His epitaph: Who, by vigor of mind almost divine, the motions and figures of the planets, the paths of comets, and the tides of the seas first demonstrated.

And from true lordship it follows that the true God is living, intelligent, and powerful; from the other perfections, that he is supreme, or supremely perfect. He is eternal and infinite, omnipotent and omniscient; that is, he endures from eternity to eternity; and he is present from infinity to infinity; he rules all things, and he knows all things that happen or can happen.

My Design in this Book is not to explain the Properties of Light by Hypotheses, but to propose and prove them by Reason and Experiments: In order to which, I shall premise the following Definitions and Axioms.

It is the weight, not numbers of experiments that is to be regarded.

Poetry is a kind of ingenious nonsense.

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?

Thus this Earth resembles a great animall or rather an inanimate vegetable, draws in aethereal breath for its dayly refreshment and vitall ferment and transpires again grosses exhalations. And, according to the condition of all other things living, ought to have its time of beginning, youth, old age and perishing.

OUR ORDINATION: Sir Isaac Newton, 1642 – 1747 About the times of the End, a body of men will be raised up who will turn their attention to the prophecies, and insist upon their literal interpretation, in the midst of much clamor and opposition.

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

In experimental philosophy, propositions gathered from phenomena by induction should be considered either exactly or very nearly true notwithstanding any contrary hypotheses, until yet other phenomena make such propositions either more exact or liable to exceptions.

I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.

I can measure the motion of bodies but I cannot measure human folly.

I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses; for whatever is not deduced from the phenomena is to be called a hypothesis, and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy.

The motions of the comets are exceedingly regular, and they observe the same laws as the motions of the planets, but they differ from the motions of vortices in every particular and are often contrary to them.

It may be that there is no such thing as an equable motion, whereby time may be accurately measured. All motions may be accelerated or retarded, but the true, or equable, progress of absolute time is liable to no change.

The smaller the planets are, they are, other things being equal, of so much the greater density; for so the powers of gravity on their several surfaces come nearer to equality. They are likewise, other things being equal, of the greater density, as they are nearer to the sun.

We are certainly not to relinquish the evidence of experiments for the sake of dreams and vain fictions of our own devising; nor are we to recede from the analogy of Nature, which is wont to be simple and always consonant to itself.

Sir Isaac Newton was asked how he discovered the law of gravity. He replied, "By thinking about it all the time.

Every action has an equal and opposite reaction