René Descartes Quotes

...it is a mark of prudence never to place our complete trust in those who have deceived us even once.

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, in each of us...

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 whole edifice that I had subsequently based on them. I realized that it was necessary, once in the course of my life, to demolish everything completely and start again right from the foundations if I wanted to establish anything at all in the sciences that was stable and likely to last.

The reading of all good books is indeed like a conversation with the noblest men of past centuries who were the authors of them, nay a carefully studied conversation, in which they reveal to us none but the best of their thoughts.

Good sense is the most equitably distributed of all things because no matter how much or little a person has, everyone feels so abundantly provided with good sense that he feels no desire for more than he already possesses.

But I cannot forget that, at other times I have been deceived in sleep by similar illusions; and, attentively considering those cases, I perceive so clearly that there exist no certain marks by which the state of waking can ever be distinguished from sleep, that I feel greatly astonished; and in amazement I almost persuade myself that I am now dreaming.

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 success, but merely being willing to risk the experiment of finding whether the truth they seek lies there.

It is not enough to have a good mind. The main thing is to use it well.

I doubt, therefore I think, therefore I am.

Bad books engender bad habits, but bad habits engender good books.

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

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

But what then am I? A thing that thinks. What is that? A thing that doubts, understand, affirms, denies, wills, refuses, and that also imagines and senses.

Whatever I have up till now accepted as most true and assured I have gotten either from the senses or through the senses. But from time to time I have found that the senses deceive, and it is prudent never to trust completely those who have deceived us even once.

[...] the diversity of our opinions, consequently, does not arise from some being endowed with a larger share of reason than others, but solely from this, that we conduct our thoughts along different ways, and do not fix our attention on the same objects. For to be possessed of a vigorous mind is not enough; the prime requisite is rightly to apply it. The greatest minds, as they are capable of the highest excellences, are open likewise to the greatest aberrations; and those who travel very slowly may yet make far greater progress, provided they keep always to the straight road, than those who, while they run, forsake it.