It is best not to go on for great quest for truth , it will only make you miserable.

I am accustomed to sleep and in my dreams to imagine the same things that lunatics imagine when awake..

Neither the true nor the false roots are always real; sometimes they are imaginary; that is, while we can always imagine as many roots for each equat….

What then is the source of my errors? They are owing simply to the fact that, since the will extends further than the intellect, I do not contain the….

By 'God', I understand, a substance which is infinite, independent, supremely intelligent, supremely powerful, and which created both myself and ever….

And as it is the most generous souls who have most gratitude, it is those who have most pride, and who are most base and infirm, who most allow thems….

I am thinking, therefore I exist. (...) I was a substance whose whole essence or nature is solely to think, and which does not require any place, or ….

If ... it is not in my power to arrive at the knowledge of any truth, I may at least do what is in my power, namely, suspend judgement..

Desire awakens only to things that are thought possible..

Thus each truth discovered was a rule available in the discovery of subsequent ones..

Human wisdom remains always one and the same although applied to the most diverse objects and it is no more changed by their diversity than the sunsh….

In God there is an infinitude of things which I cannot comprehend, nor possibly even reach in any way by thought; for it is the nature of the infinit….

Sensations are nothing but confused modes of thinking..

There is a little gland in the brain in which the soul exercises its functions in a more particular way than in the other parts..

I suppose therefore that all things I see are illusions; I believe that nothing has ever existed of everything my lying memory tells me. I think I ha….

So blind is the curiosity by which mortals are possessed, that they often conduct their minds along unexplored routes, having no reason to hope for s….

Nothing is more fairly distributed than common sense: no one thinks he needs more of it than he already has..

It is possible that I am dreaming right now and that all of my perceptions are false..

Common sense is the best distributed thing in the world, for we all think we possess a good share of it..

But in my opinion, all things in nature occur mathematically..

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….