I should consider that I know nothing about physics if I were able to explain only how things might be, and were unable to demonstrate that they coul….

It is contrary to reasoning to say that there is a vacuum or space in which there is absolutely nothing..

The greatest minds are capable of the greatest vices as well as of the greatest virtues..

Some years ago I was struck by the large number of falsehoods that I had accepted as true in my childhood, and by the highly doubtful nature of the w….

Each problem that I solved became a rule, which served afterwards to solve other problems..

There is a difference between happiness, the supreme good, and the final end or goal toward which our actions ought to tend. For happiness is not the….

I desire to live in peace and to continue the life I have begun under the motto 'to live well you must live unseen.

The senses deceive from time to time, and it is prudent never to trust wholly those who have deceived us even once..

There is nothing so far removed from us as to be beyond our reach, or so hidden that we cannot discover it..

You just keep pushing. You just keep pushing. I made every mistake that could be made. But I just kept pushing..

Be that as it may, there is fixed in my mind a certain opinion of long standing, namely that there exists a God who is able to do anything and by who….

Divide each difficulty at hand into as many pieces as possible and as could be required to better solve them..

Because reason...is the only thing that makes us men, and distinguishes us from the beasts, I would prefer to believe that it exists, in its entirety….

Neither divine grace nor natural knowledge ever diminishes freedom..

I can doubt everything, except one thing, and that is the very fact that I doubt. Simply put - I think, therefore I am.

Even if I were to suppose that I was dreaming and whatever I saw or imagined was false, yet I could not deny that ideas were truly in my mind..

Situations in life often permit no delay; and when we cannot determine the course which is certainly best, we must follow the one which is probably t….

How do we know that anything really exists, that anything is really the way it seems ot us through our senses?.

I concluded that I might take as a general rule the principle that all things which we very clearly and obviously conceive are true: only observing, ….

And thereby make ourselves, as it were, the lords and masters of nature..

For how do we know that the thoughts which occur in dreaming are false rather than those others which we experience when awake, since the former are ….