Charles Sanders Peirce Quotes

I might as well doubt of my own being, as of the being of those things I actually see and feel.

The presence of those seeking the truth is infinitely to be preferred to the presence of those who think they've found it.

We'd all like to be certain of what we know, but I think the most important question is to ask yourself do you really know what you know?

By doubting we come to questioning, and by questioning we perceive the truth.

I did not imitate the skeptics who doubt only for doubting's sake, and pretend to be always undecided; on the contrary, my whole intention was to arrive at a certainty, and to dig away the drift and the sand until I reached the rock or the clay beneath.

Everyone who observes himself doubting observes a truth, and about that which he observes he is certain; therefore he is certain about a truth. Everyone therefore who doubts whether truth exists has in himself a truth on which not to doubt.... Hence one who can doubt at all ought not to doubt the existence of truth.

Belief in truth begins with doubting all that has hitherto been believed to be true.

Truth will have no gods before it.- The belief in truth begins with the doubt of all truths in which one has previously believed.

Belief is not the beginning of knowledge - it is the end.

I have throughout been curious about how much we can be said to know and with what degree of certainty or doubtfulness.

Can I reject everything my brain experienced? Is intellectual understanding any understanding at all?

There is no permanence in doubt; it incites the mind to closer inquiry and experiment, from which, if rightly managed, certainty proceeds, and in this alone can man find thorough satisfaction.

...I will not allow books to prove any thing." "But how shall we prove any thing?" "We never shall.

Inquiry is fatal to certainty.

Skepticism is the first step on the road to philosophy.

I had therefore to remove knowledge, in order to make room for belief.

By doubting we are led to question, by questioning we arrive at the truth.

The first precept was never to accept a thing as true until I knew it as such without a single doubt.

I'm a strict, strict agnostic. It's very different from a casual, 'I don't know.' It's that you cannot present as knowledge something that is not knowledge. You can present it as faith, you can present it as belief, but you can't present it as fact.

There's nothing you can know that isn't known.

Doubt is the incentive to truth and inquiry leads the way.

If you would be a real seeker after truth, you must at least once in your life doubt, as far as possible, all things.

'Belief' means something that you do not know. You want to assume and bring a certainty to something that you do not know. That means you are concretising your ignorance. There is no need to believe anything.

In philosophy you're never 100% sure. You're always undermining what you think you know. That's always been my philosophy and my intellectual ethos.

What difference, if you are mistaken? For if I am mistaken, I am. For he who is not, assuredly cannot be mistaken; and therefore I am, if I am mistaken. Therefore because I am if I am mistaken, how am I mistaken that I am, when it is sure that I am, if I am mistaken.