We never understand a thing so well,and make it our own, as when we have discovered it for ourselves.

In the matter of a difficult question it is more likely that the truth should have been discovered by the few than by the many.

If I found any new truths in the sciences, I can say that they follow from, or depend on, five or six principal problems which I succeeded in solving and which I regard as so many battles where the fortunes of war were on my side.

Let whoever can do so deceive me, he will never bring it about that I am nothing, so long as I continue to think I am something.

Sensations are nothing but confused modes of thinking.

We never understand a thing so well,and make it our own, as when we have discovered it for ourselves.

The only thing we have power over in the universe is our own thoughts.