The sole object of Logic is the guidance of one's own thoughts: the communication of those thoughts to others falls under the consideration of Rhetoric, in the large sense in which that art was conceived by the ancients; or of the still more extensive art of Education.

The “experience” which we need to understand logic is not that such and such is the case, but that something is; but that is no experience. Logic precedes every experience — that something is so. It is before the How, not before the What.

Logic, n. The art of thinking and reasoning in strict accordance with the limitations and incapacities of the human misunderstanding. The basic of logic is the syllogism, consisting of a major and a minor premise and a conclusion - thus:

Major Premise: Sixty men can do a piece of work sixty times as quickly as one man.
Minor Premise: One man can dig a post-hole in sixty seconds; Therefore-
Conclusion: Sixty men can dig a post-hole in one second.

This may be called syllogism arithmetical, in which, by combining logic and mathematics, we obtain a double certainty and are twice blessed.

Logic is not a theory but a reflexion of the world.

Logic is the necessary product of intelligence and sincerity. It cannot be learned. It is the child of a clear head and a good heart.

Logic is simply the language of convenient rationalization in a pseudo-science-loving civilization.

More broadly, formal logic of the sort we have been talking about does only one thing well: it allows us to take knowledge of which we are certain and apply rules that are always valid to deduce new knowledge of which we are also certain.

Some persons fancy that bias and counter-bias are favorable to the extraction of truth–that hot and partisan debate is the way to investigate. This is the theory of our atrocious legal procedure. But Logic puts its heel upon this suggestion. It irrefragably demonstrates that knowledge can only be furthered by the real desire for it, and that the methods of obstinacy, of authority and every mode of trying to reach a foregone conclusion, are absolutely of no value. These things are proved. The reader is at liberty to think so or not as long as the proof is not set forth, or as long as he refrains from examining it. Just so, he can preserve, if he likes, his freedom of opinion in regard to the propositions of geometry; only, in that case, if he takes a fancy to read Euclid, he will do well to skip whatever he finds with A, B, C, etc., for, if he reads attentively that disagreeable matter, the freedom of his opinion about geometry may unhappily be lost forever.

It is by logic that we prove, but by intuition that we discover. To know how to criticize is good, to know how to create is better

writing is primarily an exercise in logic and that words are just tools designed to do a specific job.

Classical logic believed it was possible to discover the actual structure of thought processes, and the general structures underlying the external world as well as the normative laws of the mind . . . As logic has perfected its formal rigor, logicians have ceased to interest themselves in the study of actual thought processes.

The system of logic is the realm of shadows, the world of simple essentialities, freed of all sensuous concretion. To study this science, to dwell and to labor in this realm of shadows, is the absolute culture and discipline of consciousness.

Logic is the foundation of the certainty of all the knowledge we acquire.

Logic is relative.