Quotes about logic
page 9

John Steinbeck photo
Sarvepalli Radhakrishnan photo

“We invent by intuition, though we prove by logic.”

Sarvepalli Radhakrishnan (1888–1975) Indian philosopher and statesman who was the first Vice President and the second President of India

Eminent Indians (1947)

Richard Dawkins photo

“Try some Symbolic Logic on your little Couch Potato when you go home, and see what happens.”

Robertson Davies (1913–1995) Canadian journalist, playwright, professor, critic, and novelist

Lewis Carroll in the Theatre (1994)

Chelsea Manning photo
Kevin Kelly photo

“The dynamic of our society, and particularly our new economy, will increasingly obey the logic of networks. Understanding how networks work will be the key to understanding how the economy works.”

Kevin Kelly (1952) American author and editor

Out of Control: The New Biology of Machines, Social Systems and the Economic World (1995), New Rules for the New Economy: 10 Radical Strategies for a Connected World (1999)

Paul Gauguin photo

“.. color being enigmatic in itself.... then to be logical we cannot use it any other way than enigmatically..”

Paul Gauguin (1848–1903) French Post-Impressionist artist

Source: 1890s - 1910s, The Writings of a Savage (1996), p. 145

Frank P. Ramsey photo
Elfriede Jelinek photo
Paul Cézanne photo
Kenneth Arrow photo
Hans Reichenbach photo
John Holloway photo
Sri Aurobindo photo
Paul Krugman photo
Alan Greenspan photo
Vilfredo Pareto photo
Augustus De Morgan photo

“A finished or even a competent reasoner is not the work of nature alone… education develops faculties which would otherwise never have manifested their existence. It is, therefore, as necessary to learn to reason before we can expect to be able to reason, as it is to learn to swim or fence, in order to attain either of those arts. Now, something must be reasoned upon, it matters not much what it is, provided that it can be reasoned upon with certainty. The properties of mind or matter, or the study of languages, mathematics, or natural history may be chosen for this purpose. Now, of all these, it is desirable to choose the one… in which we can find out by other means, such as measurement and ocular demonstration of all sorts, whether the results are true or not.
.. Now the mathematics are peculiarly well adapted for this purpose, on the following grounds:—
1. Every term is distinctly explained, and has but one meaning, and it is rarely that two words are employed to mean the same thing.
2. The first principles are self-evident, and, though derived from observation, do not require more of it than has been made by children in general.
3. The demonstration is strictly logical, taking nothing for granted except the self-evident first principles, resting nothing upon probability, and entirely independent of authority and opinion.
4. When the conclusion is attained by reasoning, its truth or falsehood can be ascertained, in geometry by actual measurement, in algebra by common arithmetical calculation. This gives confidence, and is absolutely necessary, if… reason is not to be the instructor, but the pupil.
5. There are no words whose meanings are so much alike that the ideas which they stand for may be confounded.
…These are the principal grounds on which… the utility of mathematical studies may be shewn to rest, as a discipline for the reasoning powers. But the habits of mind which these studies have a tendency to form are valuable in the highest degree. The most important of all is the power of concentrating the ideas which a successful study of them increases where it did exist, and creates where it did not. A difficult position or a new method of passing from one proposition to another, arrests all the attention, and forces the united faculties to use their utmost exertions. The habit of mind thus formed soon extends itself to other pursuits, and is beneficially felt in all the business of life.”

Augustus De Morgan (1806–1871) British mathematician, philosopher and university teacher (1806-1871)

Source: On the Study and Difficulties of Mathematics (1831), Ch. I.

Wallace Stevens photo

“Logos and logic, crystal hypothesis,
Incipit and a form to speak the word
And every latent double in the word,

Beau linguist.”

Wallace Stevens (1879–1955) American poet

Notes Toward a Supreme Fiction (1942), It Must Be Abstract

James K. Morrow photo
Omar Khayyám photo

“For "Is" and "Is-not" though with Rule and Line
And "Up" and "Down" by Logic I define,
Of all that one should care to fathom,
Was never deep in anything but — Wine.”

Omar Khayyám (1048–1131) Persian poet, philosopher, mathematician, and astronomer

The Rubaiyat (1120)

Ann Coulter photo

“Populism is a path that, at its outset, can look and feel democratic. But, followed to its logical conclusion, it can lead to democratic backsliding or even outright authoritarianism.”

Max Fisher American journalist

Max Fisher and Amanda Taub, “How can Populism Erode Democracy? Ask Venezuela,” The New York Times, (April 2, 2017)

Chuck Jones photo
Enoch Powell photo

“The continuance of India within the British Empire is essential to the Empire's existence and is consequently a paramount interest both of the United Kingdom and of the Dominions…for strategic purposes there is no half-way house between an India fully within the Empire and an India totally outside it…Should it once be admitted or proved that Indians cannot govern themselves except by leaving the Empire – in other words, that the necessary goal of political development for the most important section of His Majesty's non-European subjects is independence and not Dominion status – then the logically inevitable outcome will be the eventual and probably the rapid loss to the Empire of all its other non-European parts. It would extinguish the hope of a lasting union between "white" and "coloured" which the conception of a common subjectship to the King-Emperor affords and to which the development of the Empire hitherto has given the prospect of leading…In discussion of the wealth of India it is usual to forget the principal item, which is four hundred millions of human beings, for the most part belonging to races neither unintelligent nor slothful…[British policy should be to] create the preconditions of democracy and self-government by as soon as possible making India socially and economically a modern state.”

Enoch Powell (1912–1998) British politician

Memorandum on Indian Policy (16 May 1946), from Simon Heffer, Like the Roman. The Life of Enoch Powell (Phoenix, 1999), pp. 104-105.
1940s

Herbert Marcuse photo
Nick Cave photo
Robert Gascoyne-Cecil, 3rd Marquess of Salisbury photo
Ray Comfort photo

“So, a talking parrot, three hundred people flying through the sky in a big tin can called a 747, a human being growing inside another person, and men walking on the moon don't contradict logic?”

Ray Comfort (1949) New Zealand-born Christian minister and evangelist

You Can Lead an Atheist to Evidence, But You Can't Make Him Think (2009)

Pierre Duhem photo

“Logic can be patient because it is eternal.”

Pierre Duhem (1861–1916) French physicist, historian of science

ibid. p. 150 https://babel.hathitrust.org/cgi/pt?id=mdp.39015019094385;view=1up;seq=152
Notice sur les Titres et Travaux scientifiques de Pierre Duhem rédigée par lui-même lors de sa candidature à l'Académie des sciences (mai 1913)

George Long photo

“The Stoics made three divisions of philosophy, Physic, Ethic, and Logic.”

George Long (1800–1879) English classical scholar

The Philosophy of Antoninus
Context: The Stoics made three divisions of philosophy, Physic, Ethic, and Logic.... It appears, however, that this division was made before Zeno's time and acknowledged by Plato.... Logic is not synonymous with our term Logic in the narrower sense of that word.

Doris Lessing photo
Enoch Powell photo

“The Prime Minister constantly asserts that the nuclear weapon has kept the peace in Europe for the last 40 years… Let us go back to the middle 1950s or to the end of the 1940s, and let us suppose that nuclear power had never been invented… I assert that in those circumstances there would still not have been a Russian invasion of western Europe. What has prevented that from happening was not the nuclear hypothesis… but the fact that the Soviet Union knew the consequences of such a move, consequences which would have followed whether or not there were 300,000 American troops stationed in Europe. The Soviet Union knew that such an action on its part would have led to a third world war—a long war, bitterly fought, a war which in the end the Soviet Union would have been likely to lose on the same basis and in the same way as the corresponding war was lost by Napoleon, by the Emperor Wilhelm and by Adolf Hitler…
For of course a logically irresistible conclusion followed from the creed that our safety depended upon the nuclear capability of the United States and its willingness to commit that capability in certain events. If that was so—and we assured ourselves for 40 years that it was—the guiding principle of the foreign policy of the United Kingdom had to be that, in no circumstances, must it depart from the basic insights of the United States and that any demand placed in the name of defence upon the United Kingdom by the United States was a demand that could not be resisted. Such was the rigorous logic of the nuclear deterrent…
It was in obedience to it… that the Prime Minister said, in the context of the use of American bases in Britain to launch an aggressive attack on Libya, that it was "inconceivable" that we could have refused a demand placed upon this country by the United States. The Prime Minister supplied the reason why: she said it was because we depend for our liberty and freedom upon the United States. Once let the nuclear hypothesis be questioned or destroyed, once allow it to break down, and from that moment the American imperative in this country's policies disappears with it.
A few days ago I was reminded, when reading a new biography of Richard Cobden, that he once addressed a terrible sentence of four words to this House of Commons. He said to hon. Members: "You have been Englishmen." The strength of those words lies in the perfect tense, with the implication that they were so no longer but had within themselves the power to be so again. I believe that we now have the opportunity, with the dissolution of the nightmare of the nuclear theory, for this country once again to have a defence policy that accords with the needs of this country as an island nation, and to have a foreign policy which rests upon a true, undistorted view of the outside world. Above all, we have the opportunity to have a foreign policy that is not dictated from outside to this country, but willed by its people. That day is coming. It may be delayed, but it will come.”

Enoch Powell (1912–1998) British politician

Speech on Foreign Affairs in the House of Commons http://hansard.millbanksystems.com/commons/1987/apr/07/foreign-affairs (7 April 1987).
1980s

Norman Mailer photo
Herbert Marcuse photo
Auguste Rodin photo

“The landscape painter, perhaps, goes even further. It is not only in living beings that he sees the reflection of the universal soul; it is in the trees, the bushes, the valleys, the hills. What to other men is only wood and earth appears to the great landscapist like the face of a great being. Corot saw kindness abroad in the trunks of the trees, in the grass of the fields, in the mirroring water of the lakes. But there Millet read suffering and resignation.
Everywhere the great artist hears spirit answer to his spirit. Where, then, can you find a more religious man?
Does not the sculptor perform his act of adoration when he perceives the majestic character of the forms that he studies? — when, from the midst of fleeting lines, he knows how to extricate the eternal type of each being? — when he seems to discern in the very breast of the divinity the immutable models on which all living creatures are moulded? Study, for example, the masterpieces of the Egyptian sculptors, either human or animal figures, and tell me if the accentuation of the essential lines does not produce the effect of a sacred hymn. Every artist who has the gift of generalizing forms, that is to say, of accenting their logic without depriving them of their living reality, provokes the same religious emotion; for he communicates to us the thrill he himself felt before the immortal verities.”

Auguste Rodin (1840–1917) French sculptor

Art, 1912, Ch. Mystery in Art

Henry John Stephen Smith photo

“So intimate is the union between Mathematics and Physics that probably by far the larger part of the accessions to our mathematical knowledge have been obtained by the efforts of mathematicians to solve the problems set to them by experiment, and to create for each successive class phenomena a new calculus or a new geometry, as the case might be, which might prove not wholly inadequate to the subtlety of nature. Sometimes the mathematician has been before the physicist, and it has happened that when some great and new question has occurred to the experimentalist or the observer, he has found in the armory of the mathematician the weapons which he needed ready made to his hand. But much oftener, the questions proposed by the physicist have transcended the utmost powers of the mathematics of the time, and a fresh mathematical creation has been needed to supply the logical instrument requisite to interpret the new enigma.”

Henry John Stephen Smith (1826–1883) mathematician

As quoted in The Century: A Popular Quarterly (1874) ed. Richard Watson Gilder, Vol. 7, pp. 508-509, https://books.google.com/books?id=ceYGAQAAIAAJ&pg=PA508 "Relations of Mathematics to Physics". Earlier quote without citation in Nature, Volume 8 (1873), page 450.
Also quoted partially in Michael Grossman and Robert Katz, Calculus http://babel.hathitrust.org/cgi/mb?a=listis;c=216746186|Non-Newtonian (1972) p. iv. ISBN 0912938013.

Camille Paglia photo
Rousas John Rushdoony photo

“The position of Pope Paul came close to being a pan-Deism, and pan-Deism is the logical development of the virus of Hellenic thought.”

Rousas John Rushdoony (1916–2001) American theologian

Source: Writings, ‘’The One and the Many‘’ (1971), Ch. VIII-7, p. 142.

George Eliot photo

“The very reason we need logic at all is because most reasoning is not conscious at all.”

Book I, Chapter 1, p. 41
The Origin of Consciousness in the Breakdown of the Bicameral Mind (1976)

Friedrich Stadler photo
Witold Doroszewski photo
Henry Adams photo
John Zerzan photo
Rudolph Rummel photo

“Since advancing freedom of the press furthers democracy, spreading freedom of the press promotes world peace. And the reverse logic is also true. Without democracies, there will be war; without freedom of the press, democracies cannot exist.”

Rudolph Rummel (1932–2014) American academic

“Freedom of the press—a way to peace,” ASNE Bulletin (February 1989), p. 27. ASNE stands for the American Association of Newspaper Editors

Jiang Zemin photo
Will Smith photo

“Even Hitler didn't wake up going, "let me do the most evil thing I can do today." I think he woke up in the morning and using a twisted, backwards logic, he set out to do what he thought was "good." Stuff like that just needs reprogramming. … I wake up every day full of hope, positive that every day is going to be better than yesterday. And I'm looking to infect people with my positivity. I think I can start an epidemic.”

Will Smith (1968) American actor, film producer and rapper

As quoted in "Will Smith : My Work Ethic Will Make Me A Legend" by Siobhan Synnot in Daily Record (22 December 2007) http://www.dailyrecord.co.uk/entertainment/celebrity-interviews/2007/12/22/will-smith-my-work-ethic-will-make-me-a-legend-86908-20262460/
This was reported in various new stories http://www.volokh.com/posts/chain_1198541498.shtml as if Smith had declared that "Adolf Hitler was essentially a good person."
Smith responded to such misinterpretations in further statements:
It is an awful and disgusting lie. It speaks to the dangerous power of an ignorant person with a pen. I am incensed and infuriated to have to respond to such ludicrous misinterpretation. … Adolf Hitler was a vile, heinous, vicious killer responsible for one of the greatest acts of evil committed on this planet.
"Will Smith Explains Hitler Quote" by Karen Salkin in People (26 December 2007) http://www.people.com/people/article/0,,20168278,00.html; Abraham H. Foxman, National Director of the Anti-Defamation League accepting Smith's clarifications stated: "If anything, this episode serves as a reminder of the power of words, and how words can be twisted by those with hate and bigotry in their hearts to suit their own world view."

Robert K. Merton photo

“The ethos of science involves the functionally necessary demand that theories or generalizations be evaluated in [terms of] their logical consistency and consonance with facts.”

Robert K. Merton (1910–2003) American sociologist

Merton (1938) "Science and the Social Order". In: Philosophy of Science Vol 5, nr 3, p. 326

Lyndall Urwick photo
Marshall McLuhan photo

“The world of visual perspective is one of unified and homogeneous space. Such a world is alien to the resonating diversity of spoken words. So language was the last art to accept the visual logic of Gutenberg technology, and the first to rebound in the electric age.”

Marshall McLuhan (1911–1980) Canadian educator, philosopher, and scholar-- a professor of English literature, a literary critic, and a …

Source: 1960s, The Gutenberg Galaxy (1962), p. 136

Arlen Specter photo

“There is just no sensible, logical reason why we would not make use of stem cell research.”

Arlen Specter (1930–2012) American politician; former United States Senator from Pennsylvania

Promoting a proposed new bill; reported in " Senate poised to pass stem cell bill http://www.msnbc.msn.com/id/13903040/", NBC News (July 17, 2006).

Amit Chaudhuri photo

“Tagore claims that the first time he experienced the thrill of poetry was when he encountered the children’s rhyme ‘Jal pare/pata nare’ (‘Rain falls / The leaf trembles') in Iswarchandra Vidyasagar’s Bengali primer Barna Parichay (Introducing the Alphabet). There are at least two revealing things about this citation. The first is that, as Bengali scholars have remarked, Tagore’s memory, and predilection, lead him to misquote and rewrite the lines. The actual rhyme is in sadhu bhasha, or ‘high’ Bengali: ‘Jal paritechhe / pata naritechhe’ (‘Rain falleth / the leaf trembleth’). This is precisely the sort of diction that Tagore chose for the English Gitanjali, which, with its thees and thous, has so tried our patience. Yet, as a Bengali poet, Tagore’s instinct was to simplify, and to draw language closer to speech. The other reason the lines of the rhyme are noteworthy, especially with regard to Tagore, is – despite their deceptively logical progression – their non-consecutive character. ‘Rain falls’ and ‘the leaf trembles’ are two independent, stand-alone observations: they don’t necessarily have to follow each other. It’s a feature of poetry commented upon by William Empson in Some Versions of Pastoral: that it’s a genre that can get away with seamlessly joining two lines which are linked, otherwise, tenuously.”

Amit Chaudhuri (1962) contemporary Indian-English novelist

On Tagore: Reading the Poet Today (2012)

“In many ways it is true to say that syntax is mathematical logic, semantics is philosophy or philosophy of science, and pragmatics is psychology, but these fields are not really all distinct.”

Frank Honywill George (1921–1997) British psychologist

Source: The Brain As A Computer (1962), p.42 as cited in: Sica Pettigiani (1996) La comunicazione interumana. p.48

John Stuart Mill photo
Franz Marc photo
Philip K. Dick photo
Conrad Aiken photo
Otto Weininger photo
Otto Weininger photo
George Holmes Howison photo

“[T]he word "eternal" must by him be taken to stand for what "temporal" does not and cannot stand for; namely, the unchangeable Ground presupposed by the changing temporal; the necessary as against the contingent; the independent as against the dependent; the primary as against the derivative; the self-existent as against that which exists in and through it; the genuine cause, the causa sui, as against that which is after all nothing but effect, however it may be tied, by the causa sui, in an unrupturable chain of antecedent and consequent. Or we may say it means the noumenon as against the phenomenon; or, in fine, the thing in itself as against the thing in other. That is, the relation between the eternal and the temporal is not, and cannot be, only another case of the temporal relation. The relation is just one of pure reason, and is, in fact, sui generis: the eternal does not precede the temporal by date, but only in logic; it is the sine qua non without which the temporal cannot exist, nor is even conceivable. In brief, throughout my book I mean by the "eternal" simply the Real as contrasted with the apparent; the world of self-active causes as contrasted with the world of derivative effects, in so far passive.”

George Holmes Howison (1834–1916) American philosopher

Source: The Limits of Evolution, and Other Essays, Illustrating the Metaphysical Theory of Personal Ideaalism (1905), Appendix D: Reply to a Review in the New York Tribune, p.412-3

Noam Chomsky photo

“Independent nationalism is unacceptable to the West, no matter where it is, and it has to be driven back into subordination. In the case of Grenada, you can do it in a weekend; in the case of the Soviet Union it may take 70 years. But these are matters of scale, the logic is essentially the same.”

Noam Chomsky (1928) american linguist, philosopher and activist

Forum with John Pilger and Harold Pinter in Islington, London, May 1994 https://web.archive.org/web/20000823015510/http://www.redpepper.org.uk/cularch/xalmeida.html.
Quotes 1990s, 1990-1994

Charles Sanders Peirce photo
Jeremy Corbyn photo
Paulo Freire photo

“Founding itself upon love, humility, and faith, dialogue becomes a horizontal relationship of which mutual trust between the dialoguers is a logical consequence.”

Paulo Freire (1921–1997) educator and philosopher

Pedagogia do oprimido (Pedagogy of the Oppressed) (1968, English trans. 1970)

Benito Mussolini photo
Max Wertheimer photo
Sviatoslav Richter photo
George Long photo
Nigel Cumberland photo

“You might find the idea of listening to your gut feelings odd or even ridiculous. Some people I coach, normally left-brain individuals who use logic and facts all day like engineers or accountants, are not used to following their intuition and feelings. Instead of asking themselves ‘What do I feel?’, they are more comfortable asking ‘What do the facts tell me?”

Nigel Cumberland (1967) British author and leadership coach

Your Job-Hunt Ltd – Advice from an Award-Winning Asian Headhunter (2003), Successful Recruitment in a Week (2012) https://books.google.ae/books?idp24GkAsgjGEC&printsecfrontcover&dqnigel+cumberland&hlen&saX&ved0ahUKEwjF75Xw0IHNAhULLcAKHazACBMQ6AEIGjAA#vonepage&qnigel%20cumberland&ffalse, 100 Things Successful People Do: Little Exercises for Successful Living (2016) https://books.google.ae/books?idnu0lCwAAQBAJ&dqnigel+cumberland&hlen&saX&ved0ahUKEwjF75Xw0IHNAhULLcAKHazACBMQ6AEIMjAE

Herbert Marcuse photo
Richard Dawkins photo

“Those people who think sexual abuse is a black-or-white, all-or-none category are incapable of clear, logical thought.”

Richard Dawkins (1941) English ethologist, evolutionary biologist and author

https://twitter.com/RichardDawkins/status/282854320133775360
Twitter

Philip Oakey photo
Florian Cajori photo
Calvin Coolidge photo

“It needs but very little consideration to reach the conclusion that all of these terms are relative, not absolute, in their application to the affairs of this earth. There is no absolute and complete sovereignty for a State, nor absolute and complete independence and freedom for an individual. It happened in 1861 that the States of the North and the South were so fully agreed among themselves that they were able to combine against each other. But supposing each State of the Union should undertake to make its own decisions upon all questions, and that all held divergent views. If such a condition were carried to its logical conclusion, each would come into conflict with all the others, and a condition would arise which could only result in mutual destruction. It is evident that this would be the antithesis of State sovereignty. Or suppose that each individual in the assertion of his own independence and freedom undertook to act in entire disregard of the rights of others. The end would be likewise mutual destruction, and no one would be independent and no one would be free. Yet these are conflicts which have gone on ever since the organization of society into government, and they are going on now. To my mind this was fundamental of the conflict which broke out in 1861.”

Calvin Coolidge (1872–1933) American politician, 30th president of the United States (in office from 1923 to 1929)

1920s, Freedom and its Obligations (1924)

William Stanley Jevons photo
Sun Myung Moon photo

“My dream is to organize a Christian political party including the Protestant denominations, Catholics and all the religious sects. Then, the communist power will be helpless before ours. We are going to do this because the communists are coming to the political scene. Before the pulpit, all the ministers of the established churches must give their sermon on how to smash or absorb communism — but they are not doing that. We are going to do this. Unless we lay the foundation for this, we cannot carry it out. In the Medieval Ages, they had to separate from the cities — statesmanship from the religious field — because people were corrupted at that time. But when it comes to our age, we must have an automatic theocracy to rule the world. So, we cannot separate the political field from the religious. Democracy was born because people ruled the world, like the Pope does. Then, we come to the conclusion that God has to rule the world, and God loving people have to rule the world — and that is logical. We have to purge the corrupted politicians, and the sons of God must rule the world. The separation between religion and politics is what Satan likes most.”

Sun Myung Moon (1920–2012) Korean religious leader

Master Speaks: The Significance of the Training Session (1973-05-17 http://www.tparents.org/Moon-Talks/sunmyungmoon73/SM730517.htm)
Note that the phrase "automatic theocracy" is seen within the church as a translation error. Mrs. Won Pok Choi, while translating the extemporaneous speech, compressed several minutes of Rev. Moon's exposition about the process by which the world would become transformed into the kingdom of heaven into this two-word phrase. Critics used to use this quote to "prove" their claim that Rev. Moon was dictatorial and anti-democratic, but Andrew Wilson had the recorded speech re-translated and exposed the discrepancy. Here is the word-for-word re-translation:[citation needed]
: What? Separate religion from politics? Why separate religion from politics? Why separate politics from religion? Can you separate God from politics? God is active in the realization of all human affairs. Therefore, when the democracies produce a succession of many uncorrupted politicians, it will become heaven on earth. Don't you agree that this is the way it should be?

Richard Huelsenbeck photo

“The dissection of words into sounds is contrary to the purpose of language and applies musical principles to an independent realm whose symbolism is aimed at a logical comprehension of one’s environment.... the value of language depends on comprehensibility rather than musicality”

Richard Huelsenbeck (1892–1974) German poet

as quoted in The Sound of Poetry / The poetry of Sound, ed. Marjorie Perloff & Craig Dworkin; University of Chicago Press, 2009, p. 310, note 22
a critic on the sound-poetry of Dadaist Hugo Ball

Ernst Schröder photo
Stephen Fry photo
Arthur Stanley Eddington photo

“The laws of logic do not prescribe the way our minds think; they prescribe the way our minds ought to think.”

Arthur Stanley Eddington (1882–1944) British astrophysicist

V, p.55
Science and the Unseen World (1929)

T. E. Lawrence photo
Colin Wilson photo
Alain de Botton photo

“Arguments are like eels: however logical, they may slip from the minds weak grasp unless fixed there by imagery and style.”

Source: The Consolations of Philosophy (2000), Chapter III, Consolation For Frustration, p. 92.