Deduction Quotes

“It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts.”
― Sir Arthur Conan Doyle, Sherlock Holmes

“What a lovely thing a rose is!"

He walked past the couch to the open window and held up the drooping stalk of a moss-rose, looking down at the dainty blend of crimson and green. It was a new phase of his character to me, for I had never before seen him show any keen interest in natural objects.

"There is nothing in which deduction is so necessary as religion," said he, leaning with his back against the shutters. "It can be built up as an exact science by the reasoner. Our highest assurance of the goodness of Providence seems to me to rest in the flowers. All other things, our powers, our desires, our food, are all really necessary for our existence in the first instance. But this rose is an extra. Its smell and its color are an embellishment of life, not a condition of it. It is only goodness which gives extras, and so I say again that we have much to hope from the flowers.”
― Arthur Conan Doyle, The Naval Treaty - a Sherlock Holmes Short Story

“Show Holmes a drop of water and he would deduce the existence of the Atlantic. Show it to me and I would look for a tap. That was the difference between us.”
― Anthony Horowitz, The House of Silk

“How did you know?”

“I…” Thomas swallowed hard, his attention fixed on the painting. “The truth?”

“Please.”

“You’ve got a dress with orchid blossoms embroidered on it. Ribbons in the deepest purple. You favor the color, but not nearly as much as I find myself favoring you.” He took a deep breath. “As to the stars? Those are what I prefer. More than medical practices and deductions. The universe is vast. A mathematical equation even I have no hope of solving. For there are no limits to the stars; their numbers are infinite. Which is precisely why I measure my love for you by them. An amount too boundless to count.”
― Kerri Maniscalco, Hunting Prince Dracula

“Dullards would have you believe that once you have eliminated the impossible, whatever remains, however improbable, must be the truth... but to a mathematical mind, the impossible is simply a theorem yet to be solved. We must not eliminate the impossible, we must conquer it, suborn it to our purpose.”
― Kim Newman, Professor Moriarty: The Hound of the D'Urbervilles

“The sensible man,' Crow had said (to Sherlock Holmes), 'don't look to confirm what he already knows -- he looks to deny it. Finding evidence that backs up your theories ain't useful, but finding evidence that your theories are wrong is priceless. Never try to prove yourself right -- always try to prove yourself wrong instead.”
― Andrew Lane, Fire Storm

“The real world was far too real to leave neat little hints. It was full of too many things. It wasn’t by eliminating the impossible that you got at the truth, however improbable; it was by the much harder process of eliminating the possibilities.”
― Terry Pratchett, Feet of Clay

“It cannot be denied that he has had many exceptional ideas, and that he is a highly intelligent man. For my part, however, I have always been taught to take a broad overview of things, in order to be able to deduce from them general rules, which might be applicable elsewhere.”
― René Descartes

“All people, whether Aspie or neuro-typical are predisposed by their society to make guesses, jump to conclusions and then seek to defend those conclusions, regardless of logic or changing circumstance. This is sloppy, illogical thinking which may not hinder your life too much, under normal circumstances. But if you want to be a great detective, then such thinking will absolutely ruin your chances.”
― Alexei Maxim Russell, Trueman Bradley - The Next Great Detective

“There's also a possibility that the landlord is in there right now, wearing women's undergarments. Or a drug addict is inside stealing jewelry.Or a boatload of recent Chinese immigrants without a television watching Russia play Finland in hockey and placing bets over beer.

You have no idea what's behind that door. You can't just pick the options within your field of vision. Reality comes from everywhere. At best, you can narrow down the likelihoods. But in the end, it's not a matter of deduction. It's a matter of fact. One bullet will kill you if you're stupid or unlucky. So at least don't be stupid”
― Derek B. Miller, Norwegian by Night

“There can be no ultimate statements science: there can be no statements in science which can not be tested, and therefore none which cannot in principle be refuted, by falsifying some of the conclusions which can be deduced from them.”
― Karl Popper

“It was quite elementary,' returned the detective with a languid gesture of one hand.”
― Anthony Horowitz, The House of Silk

“You look at me as if I were a conjuror,' Holmes remarked, with a laugh.”
― Anthony Horowitz, The House of Silk

“I find it hard enough to tackle facts, Holmes, without flying away after theories and fancies."

"You are right," said Holmes demurely: "you do find it very hard to tackle the facts.”
― Arthur Conan Doyle

“He did not dissociate his thought from himself; he thought integrally, with the whole of his body; and each logical deduction forthwith became real to him—as happens only with very healthy or direct persons who have not yet turned thought into a pastime.”
― Leonid Andreyev

“You’re making assumptions.”
“Deductions; and of course I am. It’s my duty, as your friend.”
― Rachel Hartman, Tess of the Road

“There is nothing distinctively scientific about the hypothetico-deductive process. It is not even distinctively intellectual. It is merely a scientific context for a much more general stratagem that underlies almost all regulative processes or processes of continuous control, namely feedback, the control of performance by the consequences of the act performed. In the hypothetico-deductive scheme the inferences we draw from a hypothesis are, in a sense, its logical output. If they are true, the hypothesis need not be altered, but correction is obligatory if they are false. The continuous feedback from inference to hypothesis is implicit in Whewell's account of scientific method; he would not have dissented from the view that scientific behaviour can be classified as appropriately under cybernetics as under logic.”
― Peter B. Medawar, Induction and Intuition in Scientific Thought: Memoirs, American Philosophical Society (vol. 75)

“Logical reasoning may be a most convenient means of mental communication for covering short distances, but the curvature of the earth, alas, is reflected even in logic: an ideally rational progression of thought will finally bring you back to the point of departure where you return aware of the simplicity of genius, with a delightful sensation that you have embraced truth, while actually you have merely embraced your own self... anything you might term a deduction already exposes the flaw: logical development inexorably becomes an envelopment.”
― Vladimir Nabokov, The Stories of Vladimir Nabokov

“Only an idiot guesses or reasons or deduces,’ the Professor said, patiently.”
― Kim Newman, Professor Moriarty: The Hound of the D'Urbervilles

“Reading accounts is dull; economic detective work is the easy way to get to the same conclusion.”
― Tim Harford, The Undercover Economist

“Emotional speculation is to deductive reasoning what weeds are to a garden – at first sight they appear to belong, but eventually they obscure that which one hopes will come into bud.”
― Lord Patterson Coats

“For the first time in a very many years, he felt the old vexation, the mingled impatience and pleasure at the world's beautiful refusal to yield up its mysteries without a fight.”
― Michael Chabon

“How careless of me!" By which she meant that she had deduced that he had found [them] in his pocket and pitied him for needing to be forever in the right.”
― Tom Holt, Lucia Triumphant

“There’s a disadvantage in a stick pointing straight,” answered the other. “What is it? Why, the other end of the stick always points the opposite way. It depends whether you get hold of the stick by the right end.”
― G.K. Chesterton, The Wisdom of Father Brown

“Behold but One in all things; it is the second that leads you astray.”
― kabir das

“It is an error to argue in front of your data. You find yourself insensibly twisting them round to fit your theories.

- The Adventure of Wisteria Lodge”
― Arthur Conan Doyle

“It's not what you look at that matters. It's what you see.”
― Henry David Thoreau

“At that moment, Ingrid remembered ‘The Five Orange Pips’ and maybe the most important thing Holmes told Watson: the observer who has thoroughly understood one link in a series of incidents should be able to accurately state all the ones, both before and after.”
― Peter Abrahams, Down the Rabbit Hole

“You see I have deduced why Sherlock has a deerstalker cap, why Arthur Conan Doyle chose it. If you some the Jack the Ripper reports the suspect is wearing a dirty deerstalker cap. I believe it is likely because the case was unsolvable he left it on Sherlock Holmes mind forever. I hate to hear him whine so I suppose I shall to return take the stupid hat off his head, that funny author put on him over a century ago.”
― C.A.A. Savastano

“The shapes of a tree capture its search for nutrients, and the search of its neighbours.”
― Monaristw