When I turn my mind's eye upon myself, I understand that I am a thing which is incomplete and dependent on another and which aspires without limit to ever greater and better things...

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.

Good sense is the most evenly distributed thing in the world; for everyone believes himself to be so well provided with it that even those who are the hardest to please in every other way do not usually want more of it than they already have.

Doubt everything.

Common sense is the best distributed commodity in the world, for every man is convinced that he is well supplied with it.

Common sense is the most widely shared commodity in the world, for every man is convinced that he is well supplied with it.

It is good to know something of the customs of different people in order to judge more soundly of our own, and so that we might not think that all that which is contrary to our own ways be ridiculous and contrary to reason, as those who have seen nothing have the habit of doing.

There is nothing so strange and so unbelievable that it has not been said by one philosopher or another.

One cannot conceive anything so strange and so implausible that it has not already been said by one philosopher or another.

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

This result could have been achieved either by his [God] endowing my intellect with a clear and distinct perception of everything about which I would ever deliberate, or simply by impressing the following rule so firmly upon my memory that I could never forget it: I should never judge anything that I do not clearly and distinctly understand.

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

It is just as valuable to be censured by friends as it is splendid to be praised by enemies. We desire praise from those who do not know us, but from friends we want the truth.

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.

Nothing can be imagined which is too strange or incredible to have been said by some philosopher.

My third maxim was to try always to master myself rather than fortune and change my desires rather than changing how things stand in the world.

The will determines itself; it should not be described as blind, any more than vision should be described as deaf.

Travelling is almost like talking with those of other centuries.

It is enough that I can understand one thing, clearly and distinctly, without another in order to be certain that one thing is distinct from the other.

Perfect numbers like perfect men are very rare.

Am I so tied to a body and senses that I am incapable of existing without them?

I doubt, therefore I think, therefore I am.

I had become aware, as early as my college days, that no opinion, however absurd and incredible can be imagined, that has not been held by one of the philosophers.

The destruction of the foundations necessarily brings down the whole edifice.

Illusory joy is often worth more than genuine sorrow.

Good sense is of all things in the world the most equally distributed, for everybody thinks he is so well supplied with it that even those most difficult to please in all other matters never desire more of it than they already possess.

For to be possessed of a vigorous mind is not enough; the prime requisite is rightly to apply it.

Dubium sapientiae initium (Doubt is the origin of wisdom).

In order to improve the mind, we ought less to learn, than to contemplate.

So far, I have been a spectator in this theatre which is the world, but I am now about to mount the stage, and I come forward masked.

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

It is a common failing of mortals to deem the more difficult the fairer.

All things in nature occur mathematically.

The dreams we imagine when we are asleep should not in any way make us doubt the truth of the thoughts we have when we are awake.

I am thinking, therefore I exist.

It seems to be just as foolish to say, 'I imagine, in order to understand more clearly what I am,' as to say, 'I am now clearly awake and I see something true, but because I do not yet see it clearly enough I shall fall asleep so that my dreams will represent it to me more truly and clearly.

The perusal of all excellent books is, as it were, to interview with the noblest men of past ages, who have written them.

Certainly no one can deny that we have such an idea of God in ourselves unless they think that there is no knowledge at all of God in human minds.

I resolv'd to faign, that all those things which ever entred into my Minde, were no more true, then the illusions of my dreams.

Conquer yourself rather than the world.

Thereafter, I showed how the greatest part of the matter of this chaos must, in accordance with these laws, dispose and arrange itself in such a way as to present the appearance of heavens.

I am like a prisoner who happens on enjoy an imaginary freedom in his dreams and who subsequently begins to suspect that he is asleep and, afraid of being awakened, conspires silently with his agreeable illusions.

Nothing is made from nothing.

Common sense is the most fairly distributed thing in the world, for each one thinks he is so well-endowed with it that even those who are hardest to satisfy in all other matters are not in the habit of desiring more of it than they already have.

Those who reason most powerfully and are the most successful at ordering their thoughts so as to make them clear and intelligible will always be best able to persuade others of what they say, even if they speak in the thickest of dialects.

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

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

The first was never to accept anything for true which I did not clearly know to be such; that is to say, carefully to avoid precipitancy and prejudice, and to comprise nothing more in my judgment than what was presented to my mind so clearly and distinctly as to exclude all ground of doubt.

There is often not so much perfection in works composed of many pieces and made by the hands of various master craftsmen as There is in those works on which but a single individual has worked.