. . . 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.
I seemed to have gained nothing in trying to educate myself unless it was to discover more and more fully how ignorant I was.
Divide each difficulty into as many parts as feasible and necessary to resolve it.
It is not good enough to have a good mind; the main thing is to use it well.
The multitude of laws frequently furnishes an excuse for the vice, and a state is better governed with a few laws which are strictly adhered to.
But what is a man? Shall I say 'a rational animal'? No: for then I should inquire what an animal is, what rationality is, and in this way one question would lead down the slope to harder ones.
To my sick little pal. I will try to knock you another homer, maybe two today.
We should never allow ourselves to be persuaded excepting by the evidence of our Reason, of our Reason and not of our imagination nor our senses.
I think, therefore I am.
. . . of all the sciences known as yet, Arithmetic and Geometry alone are free from any taint of falsity or uncertainty.
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 excellence, are open likewise to the greatest aberrations.
No opinion, however absurd and incredible, can be imagined, which has not been maintained by some one of the philosophers
Except our own thoughts, there is nothing absolutely in our power.
I observe that, whilst I thus wished to think that all was false, it was absolutely necessary that I, who thus thought, should be somewhat; and as I observed that this is truth, I think, hence, I am.* was so certain and of such evidence, that no ground of doubt, however extravagant, could be alleged by the skeptics capable of shaking it, I concluded that I might, without scruple, accept it as the first principle of philosophy of which I was in search.
* Cogito, ergo sum - usually translated, "I think, therefore I am." Cogito cogitationes, ergo sum and Cogito me cogitare, ergo sum, are the correct forms of the famous formula. -- Hanna Arendt, quoted in the New Yorker, November 21, 1977
What is there, then, that can be esteemed true? Perhaps this only, that there is nothing certain.
The chief cause of human error is to be found in prejudices picked up in childhood.
If you would be a real seeker after the truth, it is necessary that at least once in your life you doubt, as far as possible, all things.
The principle effect of the passions is that they incite and persuade the mind to will the events for which the prepare the body.
The reading of all good books is like conversation with the finest men of past centuries.
Traveling is almost like talking with men of other centuries.
Add your own favorite René Descartes quote in the comments.
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