Bertrand Russell Quotes

If you tried to doubt everything you would not get as far as doubting anything. The game of doubting itself presupposes certainty.

I've gone through most of my life not believing anything. Either I know or I don't know, or I think.

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.

Il n'est pas certain que tout soit incertain. (Translation: It is not certain that everything is uncertain.)

Truth is something that we can attempt to doubt, and then perhaps, after much exertion, discover that part of the doubt is not justified.

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

All reasoning ends in an appeal to self-evidence.

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

If all you have is faith, then you never actually know anything.

Dogmatism and skepticism are both, in a sense, absolute philosophies; one is certain of knowing, the other of not knowing. What philosophy should dissipate is certainty, whether of knowledge or ignorance.

There is only one thing about which I am certain, and that is that there is very little about which one can be certain.

Doubt is not an agreeable condition, but certainty is an absurd one.

Not to be absolutely certain is, I think, one of the essential things in rationality.

We cannot infer that because sciences of things divine and human are full of controversies and quarrels, therefore their whole subject-matter is uncertain ; for there have been many persons so enamoured of contradiction, as to turn into ridicule geometrical axioms.

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?

But is all this true?" said Brutha. Didactylos shrugged. "Could be. Could be. We are here and it is now. The way I see it is, after that, everything tends towards guesswork." "You mean you don't KNOW it's true?" said Brutha. "I THINK it might be," said Didactylos. "I could be wrong. Not being certain is what being a philosopher is all about.

Except in pure mathematics, nothing is known for certain (although much is certainly false).

Realism is punishing. Probabilistic skepticism is worse.

... I distrust manifest knowledge.

On the road halfway between faith and criticism stands the inn of reason. Reason is faith in what can be understood without faith, but it's still a faith, since to understand presupposes that there's something understandable.

If faith is a valid tool of knowledge, then anything can be true 'by faith,' and therefore nothing is true. If the only reason you can accept a claim is by faith, then you are admitting that the claim does not stand on its own merits.

We cannot begin with complete doubt.

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

There are two threats to reason, the opinion that one knows the truth about the most important things and the opinion that there is no truth about them. Both of these opinions are fatal to philosophy; the first asserts that the quest for truth is unnecessary, while the second asserts that it is impossible. The Socratic knowledge of ignorance, which I take to be the beginning point of all philosophy, defines the sensible middle ground between two extremes.