Logic Quotes

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But, indeed, the science of logic and the whole framework of philosophical thought men have kept since the days of Plato and Aristotle, has no more essential permanence as a final expression of the human mind, than the Scottish Longer Catechism.

The inclination to believe in the fantastic may strike some as a failure in logic, or gullibility, but it's really a gift. A world that might have Bigfoot and the Loch Ness Monster is clearly superior to one that definitely does not.

Chris Van Allsburg

It does not matter how many people chose moral duty over the rationality of self-preservation, what does matter is that some did. Evil is not all-powerful. It can be resisted. The testimony of the few who did resist shatters the authority of the logic of self-preservation. It shows it for what it is in the end: a choice.

During our session, I told Tove about how I'd done mind-speak on Duncan, but it only worked when I was irritated. Using that logic, Tove spent most of the morning trying to irritate me into using it. Sometimes it worked, but most of the time I just got pointlessly annoyed.

As the little boy said when asked if he wanted to be a lawyer like his mother, "Oh no, that's women's work." Logic has nothing to do with oppression.

Attitude lies somewhere between emotion and logic. It's that curious mix of optimism and determination that enables you to maintain a positive outlook and to continue plodding in the face of the most adverse circumstances.

The Elements has been considered as offering models of scrupulously rigorous demonstrations. It is certainly true that in point of rigour it compares favourably with its modern rivals; but when examined in the light of strict mathematical logic, it has been pronounced by C. S. Peirce to be "riddled with fallacies." The results are correct only because the writer's experience keeps him on his guard.

Common sense is science exactly in so far as it fulfills the ideal of common sense; that is, sees facts as they are, or at any rate, without the distortion of prejudice, and reasons from them in accordance with the dictates of sound judgment. And science is simply common sense at its best, that is, rigidly accurate in observation, and merciless to fallacy in logic.

Thomas Henry Huxley

And, what is worse, the reader often shares the writer's prejudices, and is far too well pleased with his conclusions to examine either his premises or his reasoning. Stand on a barrel in the streets of Bagdad, and say in a loud voice, 'Twice two is four, and ginger is hot in the mouth, therefore Mohammed is the prophet of God', and your logic will probably escape criticism; or, if anyone should by chance criticise it, you could easily silence him by calling him a Christian dog.

Scientists actively approach the door to knowledge—the boundary of the domain of what we know. We question and explore and we change our views when facts and logic force us to do so. We are confident only in what we can verify through experiments or in what we can deduce from experimentally confirmed hypotheses.

The knowledge of the theory of logic has no tendency whatever to make men good reasoners.

Thomas Babington Macaulay

Why? Hamilton lashed out suddenly and loudly. Why the hell did God answer that prayer? Why not some of the others? Why not Bill Laws's?
God approved of your prayer, Silky said. After all, it's up to Him; He has to decide how He feels about it.
That's terrible.
Silky shrugged. Maybe so.
How can you live with that? You never know what's going to happen—there's no order, no logic. It infuriated him that she did not object, that it seemed natural to her. We're helpless; we have to depend on whim. It keeps us from being people—we're like animals waiting to be fed. Rewarded or punished.

You're people, in short, who must be stupid, insane, or evil to continue arguing — in the face of indisputable facts and irrefutable logic — that others must be forced into a state of helplessness and victimized by individual criminals or the state.
Stupid, insane, or evil.

Value has its own logic. In the constitutional state that is most clearly recognizable in the enactment of its constitution.

What's at the heart of all sales and marketing: creating demand even in the absence of logic.

The logic: Reading is a private pursuit, one that often takes place behind closed doors. A young lady might retreat with a book, might even take it into her boudoir, and there, reclining on here silken sheets, imbibing the thrills and chills manufactured by writerly quills, one of her hands, one not absolutely needed to grip the little volume, might wander. The fear, in short, as one-handed reading.

[A way] one could repair Social Security... [would be to] gradually increase the retirement age. This does have a certain logic to it: the average American's life expectancy has risen by more than ten years since Social Security was created. Increasing the retirement age by even one or two years would help get the system closer to sustainability.

Mystical experience of nature can be of particular relevance to our troubled age, bringing deeper into our consciousness and emotions the logic that nature sustains humanity as humanity must, in turn, sustain nature. Rationality alone, however, cannot be our guide in the task of restoring our environment. A spiritual connection to nature must inspire the emotional commitment that is the yin, complementing the yang of intellectual understanding.

Aillas replied that while King Audry cited several points of technical interest, and used the resources of abstract logic in an adroit manner, he had actually made no connection with reality.

It has been a long road from Plato's Meno to the present, but it is perhaps encouraging that most of the progress along that road has been made since the turn of the twentieth century, and a large fraction of it since the midpoint of the century. Thought was still wholly intangible and ineffable until modern formal logic interpreted it as the manipulation of formal tokens. And it seemed still to inhabit mainly the heaven of Platonic ideals, or the equally obscure spaces of the human mind, until computers taught us how symbols could be processed by machines.

Because of the "all-or-none" character of nervous activity, events and the relations among them can be treated by means of propositional logic. It is found that the behaviour of every net can be described in these terms, with the addition of more complicated logical means for nets containing cycles; and that for any logical expression satisfying certain conditions, one can find in net behaving ever fashion it describes.

Warren S. McCulloch

The difference between prose logic and poetic thought is simple. The logician uses words as a builder uses bricks, for the unemotional deadness of his academic prose; and is always coining newer, deader words with a natural preference for Greek formations.

One cannot, however, avoid saying a few words about individuals who lay down the law to art in the name of art history. Art criticism today is beset by art historians turned inside out to function as prophets of so-called inevitable trends. A determinism similar to that projected into the evolution of past styles is clamped upon art in the making. In this parody of art history, value judgments are deduced from a presumed logic of development, and an ultimatum is issued to artists either to accommodate themselves to these values or be banned from the art of the future.

Harold Rosenberg

There is no smoke without fire, and there is no ethically repugnant principle without logic.

Anthony Daniels

The subversive character of truth inflicts upon thought an imperative quality. Logic centers on judgments which are, as demonstrative propositions, imperatives, — the predicative is implies an ought. … Verification of the proposition involves a process in fact as well as in thought: (S) must become that which it is. The categorical statement thus turns into a categorical imperative; it does not state a fact but the necessity to bring about a fact. For example, it could be read as follows: man is not (in fact) free, endowed with inalienable rights, etc., but he ought to be.

Herbert Marcuse