Charles Sanders Peirce Quotes

Logic is the art of convincing us some truth.

If someone doesn’t value evidence, what evidence are you going to provide that proves they should value evidence. If someone doesn’t value logic, what logical argument would you invoke to prove they should value logic?

There are those who reason well, but they are greatly outnumbered by those who reason badly.

Logic never attracts men to the point of carrying them away.

Rhetoric is the counterpart of logic; since both are conversant with subjects of such a nature as it is the business of all to have a certain knowledge of, and which belong to no distinct science. Wherefore all men in some way participate of both; since all, to a certain extent, attempt, as well to sift, as to maintain an argument; as well to defend themselves, as to impeach.

Geometry is the art of correct reasoning from incorrectly drawn figures.

Rationality is the recognition of the fact that nothing can alter the truth and nothing can take precedence over that act of perceiving it.

Talk about rationality can get very confusing unless the things with which rationality deals are also included.

Reason is non-negotiable. Try to argue against it, or to exclude it from some realm of knowledge, and you've already lost the argument, because you're using reason to make your case. ... We don't "believe" in reason.

One cannot refute what one has not thoroughly understood.

I hope you become comfortable with the use of logic without being deceived into concluding that logic will inevitably lead you to the correct conclusion.

Whoever in debate quotes authority uses not intellect, but memory.

Abstract truth is the eye of reason.

Logic is the art of making truth prevail.

Bein logical gave me a reason to doubt

"True science has no belief," says Dr. Fenwick, in Bulwer-Lytton's 'Strange Story;' "true science knows but three states of mind: denial, conviction, and the vast interval between the two, which is not belief, but the suspension of judgment." Such, perhaps, was true science in Dr. Fenwick's days. But the true science of our modern times proceeds otherwise; it either denies point-blank, without any preliminary investigation, or sits in the interim, between denial and conviction, and, dictionary in hand, invents new Graeco-Latin appellations for non-existing kinds of hysteria!

A skeptic, I would ask for consistency first of all.

That's the beauty of argument, if you argue correctly, you're never wrong.

Rationalism is an adventure in the clarification of thought.

Remember this: one can be a strict logician or grammarian and at the same time full of imagination and music.

There is a mighty big difference between good sound reasons and reasons that sound good.

Mathematics is a language plus reasoning. It's like a language plus logic. Mathematics is a tool for reasoning.

Problems may be solved in the study which have baffled all those who have sought a solution by the aid of their senses. To carry the art, however, to its highest pitch, it is necessary that the reasoner should be able to use all the facts which have come to his knowledge; and this in itself implies, as you will readily see, a possession of all knowledge, which, even in these days of free education and encyclopaedias, is a somewhat rare accomplishment.

With method and logic one can accomplish anything.

Logic is a very beautiful thing. As long as it is not abused.