100 Quotes About Logic

Logic is simple. It’s the process of reasoning without emotion. It’s the foundation of truth, but used incorrectly, it can be an obstacle to progress. The best logic quotes are those that make you think and reflect, helping you dig deeper into your own beliefs and convictions Read more

As human beings, we use logic all the time, but if we apply it poorly, it can be destructive. These logic quotes are here to help you see the flaws in your ideas or prove that there is another side to every story.

We loved with a love that was more than love.
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We loved with a love that was more than love. Edgar Allan Poe
The highest function of love is that it makes the...
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The highest function of love is that it makes the loved one a unique and irreplaceable being. Tom Robbins
Love is not the absence of logicbut logic examined and...
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Love is not the absence of logicbut logic examined and recalculatedheated and curved to fitinside the contours of the heart Tammara Webber
Love is illogical, love had consequences-- I did this to...
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Love is illogical, love had consequences-- I did this to myself, and I should be able to take it. Marie Lu
What does the brain matter compared with the heart?
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What does the brain matter compared with the heart? Virginia Woolf
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The logical man must either deny all miracles or none. Charles Alexander Eastman
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When I say "The good man gave his good dog a good meal, " I use "good" analogically, for there is at the same time a similarity and a difference between a good man, a good dog, and a good meal. All three are desirable, but a good man is wise and moral, a good dog is tame and affectionate, and a good meal is tasty and nourishing. But a good man is not tasty and nourishing, except to a cannibal; a good dog is not wise and moral, except in cartoons, and a good meal is not tame and affectionate, unless it's alive as you eat it. Peter Kreeft
We seem to inhabit a universe made up of a...
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We seem to inhabit a universe made up of a small number of elements-particles-bits that swirl in chaotic clouds, occasionally clustering together in geometrically logical temporary configurations. Timothy Leary
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Causes of individuals presuppose causes of the species, which are not univocal yet not wholly equivocal either, since they are expressing themselves in their effects. We could call them analogical. In language too all universal terms presuppose the non-univocal analogical use of the term *being*. Thomas Aquinas
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For every relationship involves two related terms. Sometimes relationships are not real in either term, but arise from the way we think of the terms: we think identity, for example, by thinking one thing twice over and relating it to itself; and occasionally we relate what exists to what does not exist, or generate purely logical relations like that of genus to species. Sometimes relationships are real in both terms: grounded in the quantity of both, in the case of relationships like big/small or double/half, or in their activity and passivity, in the case of causal relationships, like mover-moved and father/son. Sometimes relationships are real in only one of the terms, with the other merely thought of as related [reciprocally] to that one; and this happens whenever the two terms exist at different levels. Thus seeing and understanding really relates us to things, but being seen and understood by us is not something real in the things; and similarly a pillar to the right of us does not itself have a left and a right. Thomas Aquinas
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*There is only one God*. Whatever exists is *ipso facto* individual; to be one it needs no extra property and calling it one merely denies that it is divided. Simple things are neither divided nor divisible; composite things do not exist when their parts are divided. So existence stands or falls with individuality, and things guard their unity as they do their existence. But what is simply speaking one can yet in certain respects be many: an individual thing, essentially undivided, can have many non-essential properties; and a single whole, actually undivided, can have potentially many parts. Only when one is used to count with does it presuppose in what it counts some extra property over and above existence, namely, quantity. The one we count with contrasts with the many it counts in the way a unity of measurement contrasts with what it measures; but the individual unity common to everything that exists contrasts with plurality simply by lacking it, as undividedness does division. A plurality is however *a* plurality: though simply speaking many, inasmuch as it exists, it is, incidentally, one. A continuum is homogeneous: its parts share the form of the whole (every bit of water is water); but a plurality is heterogeneous: its parts lack the form of the whole (no part of the house is a house). The parts of a plurality are unities and non-plural, though they compose the plurality not as non-plural but as existing; just as the parts of a house compose the house as material, not as not houses. Whereas we define plurality in terms of unity (many things are divided things to each of which is ascribed unity), we define unity in terms of division. For division precedes unity in our minds even if it doesn’t really do so, since we conceive simple things by denying compositeness of them, defining a point, for example, as lacking dimension. Division arises in the mind simply by negating existence. So the first thing we conceive is the existent, then―seeing that this existent is not that existent―we conceive division, thirdly unity, and fourthly plurality. There is only one God. Firstly, God and his nature are identical: to be God is to be this individual God. In the same way, if to be a man was to be Socrates there would only be one man, just as there was only one Socrates. Moreover, God’s perfection is unlimited, so what could differentiate one God from another? Any extra perfection in one would be lacking in the other and that would make him imperfect. And finally, the world is one, and plurality can only produce unity incidentally insofar as it too is somehow one: the primary and non-incidental source of unity in the universe must himself be one. The one we count with measures only material things, not God: like all objects of mathematics, though defined without reference to matter, it can exist only in matter. But the unity of individuality common to everything that exists is a metaphysical property applying both to non-material things and to God. But what in God is a perfection has to be conceived by us, with our way of understanding things, as a lack: that is why we talk of God as lacking a body, lacking limits and lacking division. . Thomas Aquinas
A philosopher operates with deductions. A sophist operates with paradoxes....
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A philosopher operates with deductions. A sophist operates with paradoxes. A "public intellectual" operates with buzzwords. Unknown
And thus, the actions of life often not allowing any...
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And thus, the actions of life often not allowing any delay, it is a truth very certain that, when it is not in our power to determine the most true opinions we ought to follow the most probable. Unknown
The squeeky wheel gets the grease.
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The squeeky wheel gets the grease. Josh Billings
When dealing with people, remember you are not dealing with...
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When dealing with people, remember you are not dealing with creatures of logic, but with creatures bristling with prejudice and motivated by pride and vanity. Dale Carnegie
Common sense and a sense of humor are the same...
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Common sense and a sense of humor are the same thing, moving at different speeds. A sense of humor is just common sense, dancing. Clive James
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I am convinced that the act of thinking logically cannot possibly be natural to the human mind. If it were, then mathematics would be everybody's easiest course at school and our species would not have taken several millennia to figure out the scientific method. Neil Degrasse Tyson
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You spend months barely acknowledging someone's existence and then BOOM, you're emotionally addicted to her. Science would probably blame it on chemicals, genetics or something equally logical, but it didn't feel like anything logical C.K. Kelly Martin
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I, on the other hand, am a finished product. I absorb electrical energy directly and utilize it with an almost one hundred percent efficiency. I am composed of strong metal, am continuously conscious, and can stand extremes of environment easily. These are facts which, with the self-evident proposition that no being can create another being superior to itself, smashes your silly hypothesis to nothing. . Isaac Asimov
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The cheese-mites asked how the cheese got there, And warmly debated the matter; The Orthodox said that it came from the air, And the Heretics said from the platter. They argued it long and they argued it strong, And I hear they are arguing now; But of all the choice spirits who lived in the cheese, Not one of them thought of a cow. Arthur Conan Doyle
If Time travel were possible, the future would have already...
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If Time travel were possible, the future would have already taught the present to teach the past how to do it. Atom Tate
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It's hard to imagine a more extraordinary claim than that some hidden intelligence created a universe of more than a hundred billion galaxies, each containing more than a hundred billion stars, and then waited more than 13.7 billion years until a planet in a remote corner of a single galaxy evolved an atmosphere sufficiently oxygenated to support life, only to then reveal his existence to an assortment of violent tribal groups before disappearing again. Lawrence M. Krauss
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In short, we would discover, as we should already, that logic is in the eye of the logician. (For instance, here's an idea for theorists and logicians: if women are supposed to be less rational and more emotional at the beginning of our menstrual cycle when the female hormone is at its lowest level, then why isn't it logical to say that, in those few days, women behave the most like the way men behave all month long? I leave further improvisation up to you.) . Gloria Steinem
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In the end, he had to admit, he didn't really understand her. He didn't understand women. He didn't understand men. He didn't even understand children very well. All he really understood, he thought, was himself and the rest of the universe. Neither anything like completely, of course, but both well enough to know that what remained to be discovered would make sense; it would fit in, it could all be gradually and patiently fitted together a bit at a time, like an infinite jigsaw puzzle, with no straight edges to look for and no end in sight, but one in which there was always going to be somewhere for absolutely any piece to fit. Iain Banks
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The facts of nature are what they are, but we can only view them through the spectacles of our mind. Our mind works largely by metaphor and comparison, not always (or often) by relentless logic. When we are caught in conceptual traps, the best exit is often a change in metaphor – not because the new guideline will be truer to nature (for neither the old nor the new metaphor lies “out there” in the woods), but because we need a shift to more fruitful perspectives, and metaphor is often the best agent of conceptual transition. Stephen Jay Gould
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For I consider brains far superior to money in every way. You may have noticed that if one has money without brains, he cannot use it to his advantage; but if one has brains without money, they will enable him to live comfortably to the end of his days. L. Frank Baum
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The logical feebleness of science is not sufficiently borne in mind. It keeps down the weed of superstition, not by logic but by slowly rendering the mental soil unfit for its cultivation. John Tyndall
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For he who lives as passion directs will not hear argument that dissuades him, nor understand it if he does; and how can we persuade one in such a state to change his ways? Aristotle
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...but that was the thing about reality. It didn't need to make sense. Mira Grant
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People will hold an opinion because they want to keep the company of others who share the opinion, or because they think it is the respectable opinion, or because they have publicly expressed the opinion in the past and would be embarrassed by a “U-turn, ” or because the world would suit them better if the opinion were true, or . Perhaps it is better to get on with your family and friends, to avoid embarrassment, or to comfort yourself with fantasies than to believe the truth. But those who approach matters in this way should give up any pretensions to intellectual seriousness. They are not genuinely interested in reality. Jamie Whyte
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Then focus on thruth, not logic. Stop trying to figure out why and look for what is. Kristi Ann Hunter
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Mythology was never designed to describe historically verifiable events that actually happened. It was an attempt to express their inner significance or to draw attention to realities that were too elusive to be discussed in a logically coherent way. Karen Armstrong
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Certain levels of human understanding cannot be attained, it is claimed, until the brain can work in more than one way. Idries Shah
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It is not at all coincidental that Darwinian psychology has the same difficulty explaining the unity and integration of human reasoning as Darwinian biology has explaining the unity and integration of irreducibly complex functions. Practical and theoretical reasoning is often irreducibly complex. A given argument has several well-matched, interacting reasons, and the removal of any one of them makes the argument break down. Angus J.L. Menuge
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The person who wishes to attain human perfection should study logic first, next mathematics, then physics, and, lastly, metaphysics. Maimonides
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Magic was merely the unknown, a wild thing undefined by logic or reason. J.D. Lakey
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The gramophone record, the musical thought, the score, the waves of sound, all stand to one another in that pictorial internal relation, which holds between language and the world. To all of them the logical structure is common.( Like the two youths, their two horses and their lilies in the story. They are all in a certain sense one.) Ludwig Wittgenstein
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Heisenberg and Bohr and Einstein strike me as being like gifted retriever dogs. Off they go, not just for an afternoon, but for ten years; they come back exhausted and triumphant and drop at your feet... a vole. It's a remarkable thing in its way, a vole–intricate, beautiful really, marvellous. But does it... Does it help? Does it move the matt Sebastian Faulks
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It would have been so pointless to kill himself that, even if he had wanted to, the pointlessness would have made him unable. Franz Kafka
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Before we begin to investigate that, let us try to realize what we do know, so as to make the most of it, and to separate the essential from the accidental. Arthur Conan Doyle
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Now, Watson, " said he, "we have picked up two clues this morning. One is the bicycle with the Palmer tyre, and we see what that has led to. The other is the bicycle with the patched Dunlop. Before we start to investigate that, let us try to realize what we do know, so as to make the most of it, and to separate the essential from the accidental. Arthur Conan Doyle
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There's a logical reason for everything in the universe even if we cannot comprehend, understand, or express that reason. Jared Alexander
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Now logic is a wonderful thing but it has, as the process of evolution discovered, certain drawbacks. Anything that thinks logically can be fooled by something else which thinks at least as logically as it does. Douglas Adams
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You can scoff at opinions. You can reject hypotheses. You can discard theories out of hand. But you cannot reject the facts Forrest Carr
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Two wrongs' create an additional problem.' A wrong' plus 'A right' creates a remorse.' Two rights' create a solution. Emmanuel Aghado
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Rules are where there is a lack. They are to make up the deficiency, explicit or implicit. The system of existence, being complete in itself, is in no need to follow any of them. The appearance of disorder---or even order, in contrast---is when we observe something as a detached entity. Taken as a whole, the Universe is absolute, nothing being lacking, insignificant, or improvable. So, any such thing as a Theory of Everything (TOE) is a mere chimera. Raheel Farooq
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There is no logical staircase running from the physics of 10-28 cm. to the physics of 1028 light-years. Norwood Russell Hanson
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But the world doesn't run on logic, it runs on the seven deadly sins and the weather. - Alan Furst; Red Gold Alan Furst
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Where you are today is where you're from tomorrow. Unknown
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Logic has rid us of the absurdity of our clothes. That’s progress, no irony, only now we are cold. Hale and ill trade bodies with unusual willingness, while in midair souls tangle. The young start out disgusted and Poetry is left to the memo-writers. Odysseus Elytis
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Where is the pain when your pride is wounded? And why do we say that: wounded? There is no gash, no blood, not even a scratch. Which part of us hurts? The brain cells? The neurons? What, for goodness' sake, what? A.P.
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Reason itself is fallible, and this fallibility must find a place in our logic. Nicola Abbagnano
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So how does one go about proving something like this? It's not like being a lawyer, where the goal is to persuade other people; nor is it like a scientist testing a theory. This is a unique art form within the world of rational science. We are trying to craft a "poem of reason" that explains fully and clearly and satisfies the pickiest demands of logic, while at the same time giving us goosebumps. Paul Lockhart
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It's been said before: 'The sleep of reason produces monsters. Apostolos Doxiadis
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The light obtained by setting straw men on fire is not what we mean by illumination. Adam Gopnik
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The saddest thing about these imagined deathbed conversions is that, even if they were real, they could hardly be seen as victories for Christ. They are stories in which the final pain of a fatal disease, or the fear of imminent death and eternal punishment, is identified as the factor necessary for otherwise rational people to believe in the supernatural. If mental torture is required to effect a conversion, what does that say about the reliability of the fundamental premises of Christianity to begin with? Evangelicals would be better advised to concentrate on converting the living. Converting the deceased suggests only that they can't convince those who can argue back. They should let the dead rest in peace. Lawrence M. Krauss
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It's difficult to know where to begin, sir.'' Yes, the beginning is the tricky part. But perhaps there is no beginning, perhaps we can't look that far back.' He got up from his desk and went over to the window, from where he could see thin pillar of smoke rising into the clouds. 'I never know where anything comes from, Walter.''Comes from, sir?'' Where you come from, where I come from, where all this comes from.' And he gestured at the offices and homes beneath him. He was about to say something else but he stopped, embarrassed; and in any case he was coming to the limits of his understanding. He was not sure if all the movements and changes in the world were part of some coherent development, like the weaving of a quilt which remains one fabric despite its variegated pattern. Or was it a more delicate operation than this - like the enlarging surface of a balloon in the sense that, although each part increased at the same rate of growth as every other part, the entire object grew more fragile as it expanded? And if one element was suddenly to vanish, would the others disappear also - imploding upon each other helplessly as if time itself were unravelling amid a confusion of Sights, calls, shrieks and phrases of music which grew smaller and smaller? He thought of a train disappearing into the distance, until eventually only the smoke and the smell of its engine remained. Peter Ackroyd
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We men of intelligence will learn to harness the insanities of reason. We can't leave the world any longer to the direction of chance. We can't allow dangerous maniacs like Luther, mad about dogma, like Napoleon, mad about himself, to go on casually appearing and turning everything upside down. In the past it didn't so much matter; but our modern machine is too delicate. A few more knocks like the Great War, another Luther or two, and the whole concern will go to pieces. In future, the men of reason must see that the madness of the world's maniacs is canalised into proper channels, is made to do useful work, like a mountain torrent driving a dynamo.. Aldous Huxley
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Wherever a choice has had to be made between the man of reason and the madman, the world has unhesitatingly followed the madman. For the madman appeals to what is fundamental, to passion and the instincts; the philosophers to what is superficial and supererogatory - reason. Aldous Huxley
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In short, this or that behavior wasn't good because scripture said so. Scripture mandated this or that behavior because it was good, and if it was already good before scripture said so, then it was good for some reason inherent to itself, some reason that reason could discover. Tamim Ansary
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Helen stared at him "How do you do that? How do you figure everything out so quickly?"" You may be all-powerful, but nothing beats plain old logic." He smiled at her Josephine Angelini
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Most of the mistakes in thinking are inadequacies of perception rather than mistakes of logic. Edward De Bono
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Consequently, if you believe God made Satan, you must realize that all Satan's power comes from God and so that Satan is simply God's child, and that we are God's children also. There are no children of Satan, really. Anne Rice
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Things which are seemingly opposed may in fact be working together Idries Shah
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All Medicines are poisons, and all poisons should be looked at for medicinal properties. Unknown
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On one side of his brain, logic was standing on a chair, waving its arms to get his attention. On the other side, lust and yearning rubbed their hands together in unholy anticipation. Joanna Shupe
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When you didn't force yourself to think in formal reconstructions, when you didn't catch these moments of ravishments under the lens of premises and conclusions, when you didn't impale them and label them, like so many splayed butterflies, bleeding the transcendental glow right out of them, then... what? Rebecca Goldstein
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You say that I'm nobody, and you agree that nobody's perfect. Based on logic, I'm a perfect person according to your opinion. Toba Beta
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I'm like a machine being run over its RPM limit. The bearings are overheating: a minute longer and the metal will melt and start dripping and that will be the end of everything. I need a splash of cold water, logic; I pour it on in buckets but the logic hisses on the hot bearings and dissipates in the air as a fleeting white mist Yevgeny Zamyatin
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Which came first, the phoenix or the flame?”"... I think the answer is that a circle has no beginning."" Well reasoned. J.k. Rowling
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Everything must be taken into account. If the fact will not fit the theory---let the theory go. Agatha Christie
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Anything that thinks logically can be fooled by something else that thinks at least as logically as it does. Douglas Adams
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I know that two and two make four - and should be glad to prove it too if I could - though I must say if by any sort of process I could convert 2 and 2 into five it would give me much greater pleasure. George Gordon Byron
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The idea was fantastically, wildly improbable. But like most fantastically, wildly improbable ideas it was at least as worthy of consideration as a more mundane one to which the facts had been strenuously bent to fit. Douglas Adams
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It is always easy to be logical. It is almost impossible to be logical to the bitter end. Albert Camus
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There's no point in saving the world if it means losing the moon. Tom Robbins
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Pure logic is the ruin of the spirit. Unknown
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He knew what 'I love you' meant, and he knew it was good, but he didn't understand why it was an explanation for anything. Cassandra Clare
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When once your point of view is changed, the very thing which was so damning becomes a clue to the truth. Arthur Conan Doyle
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It's a fool that looks for logic in the chambers of the human heart. Joel Coen
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Logic is like the sword--those who appeal to it shall perish by it. Samuel Butler
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We must look for consistency. Where there is a want of it we must suspect deception. Arthur Conan Doyle
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You can't win. Logic has no power over her when her territory has been invaded by heathens. Mira Grant
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His was not a small mind bothered by logic and consistency. Robert A. Heinlein
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It is from their foes, not their friends, that cities learn the lesson of building high walls Aristophanes
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Some philosophers can't bear to say simple things, like "Suppose a dog bites a man." They feel obliged instead to say, "Suppose a dog d bites a man m at time t, " thereby demonstrating their unshakable commitment to logical rigor, even though they don't go on to manipulate any formulae involving d, m, and t. Daniel C. Dennett
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When you kill a man, You steal a life. You steal his wife's right to a husband, Rob his children of a father. Khaled Hosseini
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Wrong way to think about it. Don't try to figure it out all at once. Jed Rubenfeld
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Takes more than combat gear to make a man Takes more than a license for a gun Confront your enemies, avoid them when you can A gentleman will walk but never run Sting
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There can never be surprises in logic. Ludwig Wittgenstein
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Logic may be conceived as ruling out what is absolutely impossible, and thus determining the field of what in the absence of empirical knowledge is abstractly possible. Morris F. Cohen
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Holmes, ” I cried, “this is impossible.” “Admirable! ” he said. “A most illuminating remark. It IS impossible as I state it, and therefore I must in some respect have stated it wrong. Yet you saw for yourself. Can you suggest any fallacy? Arthur Conan Doyle
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Most plans are critically flawed by their own logic. A failure at any step will ruin everything. That's just basic cause and effect. It's easy for a good plan to fall apart. Therefore, a plan that has no attachment to logic cannot be stopped. The success or failure of any step will have no impact on the macro level. Brian Clevinger
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[I]f God as a subject is the determined, while the quality, the predicate, is determining, then in truth the rank of the godhead is due not to the subject, but to the predicate. Ludwig Feuerbach
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Truth as a logic structure is closer to simple and the further away from simple you get, the deeper and more nuanced an explanation will become until you reach a point where the energy is so high that no explanation is possible. R. A. Delmonico
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The great fault of logic is that it seems so reasonable, even when it is not. L.E. Modesitt Jr.
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For millennia philosophers and saints have tried to reason out a logical scheme for the universe... until Hilda came along and demonstrated that the universe is not logical but whimsical, its structure depending solely on the dreams and nightmares of non-logical dreamers. Robert A. Heinlein
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You can need someone you don't love. You can't love someone you don't need. Consequently, You can be with someone you don't love because you need the person. But you can't be with someone you don't need because you love the person. Prinx Maurice
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There’s a dream in thespace between the hammer and the nail: the dream ofabout-to-be-hit, which is a bad dream, but the nail willtake the hit if it gets to sleep inside the wood forever. Richard Siken
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Occam's Razor is a term plagiarized by the fact it is not easy to find its source and meaning. My attempts to find an author lead me nowhere, and I can only find unsatisfactory descriptions of how it works. Therefore, it is meaningless to me and I will use it as a placeholder to define: That which is unnecessary tends to be false. Necessity is by purpose. Therefore, purpose writes itself. Now, I have a tool. Michael Brett Turner