The Abilene paradox is a collective fallacy, in which a group of people collectively decide on a course of action that is counter to the preferences of most or all individuals in the group, while each individual believes it to be aligned with the preferences of most of the others. It involves a breakdown of group communication in which each member mistakenly believes that their own preferences are counter to the grou
The accuracy paradox is the paradoxical finding that accuracy is not a good metric for predictive models when classifying in predictive analytics. This is because a simple model may have a high level of accuracy but too crude to be useful.
Acosmism, held in contrast or equivalent to pantheism, denies the reality of the universe, seeing it as ultimately illusory (the prefix 'ἀ-' in Greek meaning negation; like 'un-' in English), and only the infinite unmanifest Absolute as real. Conceptual versions of Acosmism are found in eastern and western philosophies.
Air conditioning, often abbreviated as A/C (US) or air con (UK), is the process of removing heat from an enclosed space to achieve a more comfortable interior temperature and, in some cases, controlling the humidity of internal air. Air conditioning can be achieved using a mechanical 'air conditioner' or through other methods, such as passive cooling and ventilative cooling.
An apportionment paradox is a situation where an apportionment—a rule for dividing discrete objects according to some proportional relationship—produces results that violate notions of common sense or fairness. Certain quantities, like milk, can be divided in any proportion whatsoever; others, such as horses, cannot—only whole numbers will do.
In stellar astronomy, the Algol paradox is a paradox situation when the two stars of a binary star system appear to act opposite their cycle towards death; one star is more advanced in its stellar evolution than the other despite that star being smaller (less massive) than the other. This paradox is observed when one smaller star has already exited its main sequence form and its larger partner has not.
All horses are the same color is a falsidical paradox that arises from a flawed use of mathematical induction to prove the statement All horses are the same color. There is no actual contradiction, as these arguments have a crucial flaw that makes them incorrect.
The allegory of the cave is an allegory presented by the Greek philosopher Plato in his work Republic (514a–520a, Book VII) to compare 'the effect of education (παιδεία) and the lack of it on our nature'. It is written as a dialogue between Plato's brother Glaucon and his mentor Socrates and is narrated by the latter.
High-nutrient, low-chlorophyll (HNLC) regions are regions of the ocean where the abundance of phytoplankton is low and fairly constant despite the availability of macronutrients. Phytoplankton rely on a suite of nutrients for cellular function.
In philosophy, an aporia (Ancient Greek: ᾰ̓πορῐ́ᾱ, romanized: aporíā, lit. ''lacking passage', also: 'impasse', 'difficulty in passage', 'puzzlement'') is a conundrum or state of puzzlement. In rhetoric, it is a declaration of doubt, made for rhetorical purpose and often feigned.
An apportionment paradox is a situation where an apportionment—a rule for dividing discrete objects according to some proportional relationship—produces results that violate notions of common sense or fairness. Certain quantities, like milk, can be divided in any proportion whatsoever; others, such as horses, cannot—only whole numbers will do.
The archer's paradox is the phenomenon of an arrow traveling in the direction it is pointed at full draw, when it seems that the arrow would have to pass through the starting position it was in before being drawn, where it was pointed to the side of the target. The bending of the arrow when released is the explanation for why the paradox occurs and should not be confused with the paradox itself.
Aristotle's wheel paradox is a paradox or problem appearing in the pseudo-Aristotelian Greek work Mechanica. It states as follows: A wheel is depicted in two-dimensional space as two circles.
The ball and shot gun, often also known by the marketing name paradox gun, is a shotgun capable of firing both shot and solid projectiles. First built by Holland and Holland, the term paradox is a proprietary name applied to these guns by Holland and Holland.
The barber paradox is a puzzle derived from Russell's paradox. It was suggested to Bertrand Russell as an illustration of the paradox, but he deemed it an invalid modification of his paradox.
Bell's spaceship paradox is a thought experiment in special relativity. It was first described by E. Dewan and M. Beran in 1959 but became more widely known after John Stewart Bell elaborated the idea further in 1976.
Bellum omnium contra omnes, a Latin phrase meaning 'the war of all against all', is the description that Thomas Hobbes gives to human existence in the state-of-nature thought experiment that he conducts in De Cive (1642) and Leviathan (1651). The common modern English usage is a war of 'each against all' where war is rare and terms such as 'competition' or 'struggle' are more common.
The Berry paradox is a self-referential paradox arising from an expression like 'The smallest positive integer not definable in under sixty letters' (a phrase with fifty-seven letters). Bertrand Russell, the first to discuss the paradox in print, attributed it to G. G. Berry (1867–1928), a junior librarian at Oxford's Bodleian Library.
Bhartṛhari (Devanagari: भर्तृहरि; Bhartrihari; fl. c.
Bonini's paradox, named after Stanford business professor Charles Bonini, explains the difficulty in constructing models or simulations that fully capture the workings of complex systems (such as the human brain).
Braess's paradox is the observation that adding one or more roads to a road network can slow down overall traffic flow through it. The paradox was first discovered by Arthur Pigou in 1920, and later named after the German mathematician Dietrich Braess in 1968.
Braess's paradox is the observation that adding one or more roads to a road network can slow down overall traffic flow through it. The paradox was first discovered by Arthur Pigou in 1920, and later named after the German mathematician Dietrich Braess in 1968.
In the philosophy of mind, the Brainstorm machine is a thought experiment described by Daniel Dennett, to show that it is not possible to intersubjectively compare any two individuals' personal experiences, or qualia, even with perfect technology. It is based on a device described in the film Brainstorm, in which the visual experience of one individual is fed into the brain of another.
Isaac Newton's rotating bucket argument (also known as Newton's bucket) is a thought experiment that was designed to demonstrate that true rotational motion cannot be defined as the relative rotation of the body with respect to the immediately surrounding bodies. It is one of five arguments from the 'properties, causes, and effects' of 'true motion and rest' that support his contention that, in general, true motion a
Buridan's ass is an illustration of a paradox in philosophy in the conception of free will. It refers to a hypothetical situation wherein an ass (or donkey) that is equally hungry and thirsty is placed precisely midway between a stack of hay and a pail of water.
Buridan's Bridge (also known as Sophism 17) is described by Jean Buridan, one of the most famous and influential philosophers of the Late Middle Ages, in his book Sophismata. It is a self-referential paradox that involves a proposition pronounced about an event that might or might not happen in the future.
The buttered cat paradox is a common joke based on the combination of two adages: Cats always land on their feet. Buttered toast always lands buttered side down.
The card paradox is a variant of the liar paradox constructed by Philip Jourdain. It is also known as the postcard paradox, Jourdain paradox or Jourdain's paradox.
In the philosophy of mind, the China brain thought experiment (also known as the Chinese Nation, Chinese Gym, or China-body) considers what would happen if each person in the entire population of China were asked to simulate the action of one neuron in the brain, using telephones or walkie-talkies to simulate the axons and dendrites that connect neurons. The question this thought experiment attempts to answer is whet
The coastline paradox is the counterintuitive observation that the coastline of a landmass does not have a well-defined length or perimeter. This results from the fractal curve–like properties of coastlines, namely the fact that a coastline typically has a fractal dimension.
Coherence, also called uniformity or consistency, is a criterion for evaluating rules for fair division. Coherence requires that the outcome of a fairness rule is fair not only for the overall problem, but also for each sub-problem.
The coin rotation paradox is the counter-intuitive mathematical fact that, when one coin is rolled without slipping around the rim of another coin of equal size, the moving coin completes not one but two full rotations after going all the way around the stationary coin, when viewed from an external reference frame. The problem can be further generalized to coins of different radii.
Semelparity and iteroparity are two reproductive strategies available to living organisms. A species is semelparous if it is characterized by a single reproductive episode before death, and iteroparous if it is characterized by multiple reproductive cycles.
The cool tropics paradox is the apparent difference between modeled estimates of tropical temperatures during warm, ice-free periods of the Cretaceous and Eocene, and the colder temperatures which proxies suggested were present. The long-standing paradox was resolved when novel proxy derived temperatures showed significantly warmer tropics during past greenhouse climates.
In mathematics, Cramer's paradox or the Cramer–Euler paradox is the statement that the number of points of intersection of two higher-order curves in the plane can be greater than the number of arbitrary points that are usually needed to define one such curve. It is named after the Genevan mathematician Gabriel Cramer.
In fluid dynamics, d'Alembert's paradox (or the hydrodynamic paradox) is a paradox discovered in 1752 by French mathematician Jean le Rond d'Alembert. D'Alembert proved that – for incompressible and inviscid potential flow – the drag force is zero on a body moving with constant velocity relative to (and simultaneously through) the fluid.
In biology, Denny's paradox refers to the apparent impossibility of surface-dwelling animals such as the water strider generating enough propulsive force to move. It is named after biologist Mark Denny, and relates to animal locomotion on the surface layer of water.
In computer science, the dining philosophers problem is an example problem often used in concurrent algorithm design to illustrate synchronization issues and techniques for resolving them. It was originally formulated in 1965 by Edsger Dijkstra as a student exam exercise, presented in terms of computers competing for access to tape drive peripherals.
A Dyson sphere is a hypothetical megastructure that encompasses a star and captures a large percentage of its power output. The concept is a thought experiment that attempts to imagine how a spacefaring civilization would meet its energy requirements once those requirements exceed what can be generated from the home planet's resources alone.
The Ehrenfest paradox concerns the rotation of a 'rigid' disc in the theory of relativity. In its original 1909 formulation as presented by Paul Ehrenfest in relation to the concept of Born rigidity within special relativity, it discusses an ideally rigid cylinder that is made to rotate about its axis of symmetry.
A hallmark of Albert Einstein's career was his use of visualized thought experiments (German: Gedankenexperiment) as a fundamental tool for understanding physical issues and for elucidating his concepts to others. Einstein's thought experiments took diverse forms.
The elevator paradox is a paradox first noted by Marvin Stern and George Gamow, physicists who had offices on different floors of a multi-story building. Gamow, who had an office near the bottom of the building noticed that the first elevator to stop at his floor was most often going down, while Stern, who had an office near the top, noticed that the first elevator to stop at his floor was most often going up.
Epistemology is the branch of philosophy that examines the nature, origin, and limits of knowledge. Also called the theory of knowledge, it explores different types of knowledge, such as propositional knowledge about facts, practical knowledge in the form of skills, and knowledge by acquaintance as a familiarity through experience.
The European paradox is the perceived failure of European countries to translate scientific advances into marketable innovations. The term was coined in a European Commission Green Paper in 1995.
The exercise paradox, also known as the workout paradox, refers to the finding that physical activity, while essential for maintaining overall health, does not necessarily lead to significant weight loss or increased calorie expenditure. This paradox challenges the common belief that more exercise equates to more calories burned and consequently, more weight loss.
In the small wavelength limit, the total scattering cross-section of an impenetrable sphere is twice its geometrical cross-sectional area (which is the value obtained in classical mechanics).
The faint young Sun paradox or faint young Sun problem describes the apparent contradiction between observations of liquid water early in Earth's history and the astrophysical expectation that the Sun's output would have been only 70 percent as intense during that epoch as it is during the modern epoch. The paradox is this: with the young Sun's output at only 70 percent of its current output, early Earth would be exp
The base rate fallacy, also called base rate neglect or base rate bias, is a type of fallacy in which people tend to ignore the base rate (e.g., general prevalence) in favor of the information pertaining only to a specific case. Base rate neglect is a specific form of the more general extension neglect.
The Faraday paradox or Faraday's paradox is any experiment in which Michael Faraday's law of electromagnetic induction appears to predict an incorrect result. The paradoxes fall into two classes: Faraday's law appears to predict that there will be zero electromotive force (EMF) but there is a non-zero EMF. Faraday's law appears to predict that there will be a non-zero EMF but there is zero EMF. Faraday deduced his la
The Faraday paradox was a once inexplicable aspect of the reaction between nitric acid and steel. Around 1830, the English scientist Michael Faraday found that diluted nitric acid would attack steel, but concentrated nitric acid would not.
Fenno's paradox is the idea that people generally disapprove of the United States Congress as a whole but often support the congressmen from their own congressional districts. The paradox is named after political scientist Richard Fenno, who discussed this phenomenon in his 1978 book Home Style: House Members in Their Districts.
The Fermi paradox is the discrepancy between the lack of conclusive evidence of advanced extraterrestrial life and the apparently high likelihood of its existence. The paradox is named after physicist Enrico Fermi, who informally posed the question—remembered by Emil Konopinski as 'But where is everybody?'—during a 1950 conversation at Los Alamos with colleagues Konopinski, Edward Teller, and Herbert York.
The floating man, flying man, or man suspended in air argument is a thought experiment by the Persian philosopher Ibn Sina (Avicenna) which argues for the existence of the soul. This thought experiment is used to argue in favor of knowledge by presence.
The friendship paradox is the phenomenon first observed by the sociologist Scott L. Feld in 1991 that on average, an individual's friends have more friends than that individual. It can be explained as a form of sampling bias in which people with more friends are more likely to be in one's own friend group.
Gilbert Keith Chesterton (29 May 1874 – 14 June 1936) was an English Christian apologist writer. Chesterton's wit, paradoxical style, and defence of tradition made him a dominant figure in early 20th-century literature.
A Gabriel's horn (also called Torricelli's trumpet) is a type of geometric figure that has infinite surface area but finite volume. The name refers to the Christian idea that the archangel Gabriel will one day blow his horn to announce Judgment Day.
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The Gettier problem, in the field of epistemology, is a landmark philosophical problem concerning the understanding of descriptive knowledge. Attributed to American philosopher Edmund Gettier, Gettier-type counterexamples (called 'Gettier-cases') challenge the long-held justified true belief (JTB) account of knowledge.
The glucose paradox was the observation that the large amount of glycogen in the liver was not explained by the small amount of glucose absorbed. The explanation was that the majority of glycogen is made from a number of substances other than glucose.
In mathematics, the infinite series 1 − 1 + 1 − 1 + ⋯ is a divergent series, meaning that the sequence of partial sums of the series does not converge. Although it is divergent, it can be manipulated to yield a number of mathematically interesting results.
Gray's Paradox is a paradox posed in 1936 by British zoologist Sir James Gray. The paradox was to figure out how dolphins can obtain such high speeds and accelerations with what appears to be a small muscle mass.
The Greisen–Zatsepin–Kuzmin limit (GZK limit or GZK cutoff) is a theoretical upper limit on the energy of cosmic ray protons traveling from other galaxies through the intergalactic medium to our galaxy. The limit is 5×1019 eV (50 EeV), or about 8 joules (the energy of a proton travelling at ≈ 99.99999999999999999998% the speed of light).
Kin selection is a process whereby natural selection favours a trait due to its positive effects on the reproductive success of an organism's relatives, even when at a cost to the organism's own survival and reproduction. Kin selection can lead to the evolution of altruistic behaviour.
The Hausdorff paradox is a paradox in mathematics named after Felix Hausdorff. It involves the sphere S 2 {\\displaystyle {S^{2}}} (the surface of a 3-dimensional ball in R 3 {\\displaystyle {\\mathbb {R} ^{3}}} ).
The heat death paradox, also known as thermodynamic paradox, Clausius' paradox, and Kelvin's paradox, is a reductio ad absurdum argument that uses thermodynamics to show the impossibility of an infinitely old universe. It was formulated in February 1862 by Lord Kelvin and expanded upon by Hermann von Helmholtz and William John Macquorn Rankine.
A heuristic or heuristic technique (problem solving, mental shortcut, rule of thumb) is any approach to problem solving that employs a pragmatic method that is not fully optimized, perfected, or rationalized, but is nevertheless 'good enough' as an approximation or attribute substitution. Where finding an optimal solution is impossible or impractical, heuristic methods can be used to speed up the process of finding a
The Hilbert–Bernays paradox is a distinctive paradox belonging to the family of the paradoxes of reference. It is named after David Hilbert and Paul Bernays.
Hooper's paradox is a falsidical paradox based on an optical illusion. A geometric shape with an area of 32 units is dissected into four parts, which afterwards get assembled into a rectangle with an area of only 30 units.
Vertical pressure variation is the variation in pressure as a function of elevation. Depending on the fluid in question and the context being referred to, it may also vary significantly in dimensions perpendicular to elevation as well, and these variations have relevance in the context of pressure gradient force and its effects.
The Icarus paradox is a neologism coined by Danny Miller in his 1990 book by the same name. The term refers to the phenomenon of businesses failing abruptly after a period of apparent success, where this failure is brought about by the very elements that led to their initial success.
If a tree falls in a forest and no one is around to hear it, does it make a sound?' is a philosophical thought experiment that raises questions regarding observation and perception.
Ignore all rules' (IAR) is a policy of the English Wikipedia, an online encyclopedia, which reads: 'If a rule prevents you from improving or maintaining Wikipedia, ignore it.' (emphasis and links in original). The rule was proposed by Wikipedia co-founder Larry Sanger to encourage editors to add information without focusing excessively on formatting, though Sanger later criticized the rule's effects on the community
The impossible cube or irrational cube is an impossible object invented by M.C. Escher for his 1958 print Belvedere. It is a two-dimensional figure that superficially resembles a perspective drawing of a three-dimensional cube, with its features drawn inconsistently from the way they would appear in an actual cube.
In the Middle Ages, variations on the liar paradox were studied under the name of insolubilia ('insolubles').
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The interesting number paradox is a humorous paradox which arises from the attempt to classify every natural number as either 'interesting' or 'uninteresting'. The paradox states that every natural number is interesting.
An intuition pump is a type of thought experiment that leads the audience to a specific conclusion through intuition.
The inventor's paradox is a phenomenon that occurs in seeking a solution to a given problem. Instead of solving a specific type of problem, which would seem intuitively easier, it can be easier to solve a more general problem, which covers the specifics of the sought-after solution.
The inverted spectrum is the hypothetical scenario, pertaining to the philosophy of color, of two people sharing their color vocabulary and discriminations, although the colors one sees—that person's qualia—are systematically different from the colors the other person sees.
The irresistible force paradox (also unstoppable force paradox or shield and spear paradox), is a classic paradox formulated as 'What happens when an unstoppable force meets an immovable object?' The immovable object and the unstoppable force are both implicitly assumed to be indestructible, or else the question would have a trivial resolution. Furthermore, it is assumed that they are two entities.
Kin selection is a process whereby natural selection favours a trait due to its positive effects on the reproductive success of an organism's relatives, even when at a cost to the organism's own survival and reproduction. Kin selection can lead to the evolution of altruistic behaviour.
The Knudsen paradox has been observed in experiments of channel flow with varying channel width or equivalently different pressures. If the normalized mass flux through the channel is plotted over the Knudsen number based on the channel width a distinct minimum is observed around K n = 0.8 {\\displaystyle Kn=0.8} .
The ladder paradox (or barn-pole paradox) is a thought experiment in special relativity. It involves a ladder, parallel to the ground, travelling horizontally at relativistic speed (near the speed of light) and therefore undergoing a Lorentz length contraction.
Levinthal's paradox is a thought experiment in the field of computational protein structure prediction; protein folding is the process by which peptides reach a stable native configuration. In theory, a brute force search, testing all possible conformations, would take longer than the age of the universe to identify this minimum energy configuration (the native state).
List of unsolved problems may refer to several notable conjectures or open problems in various academic fields:
The lottery paradox arises from Henry E. Kyburg Jr. considering a fair 1,000-ticket lottery that has exactly one winning ticket.
The low birth-weight paradox is an apparently paradoxical observation relating to the birth weights and mortality rate of children born to tobacco smoking mothers. Low birth-weight children born to smoking mothers have a lower infant mortality rate than the low birth weight children of non-smokers.
Mandeville's paradox is named after Bernard Mandeville (1670–1733), who posits that actions which may be qualified as vicious with regard to individuals have benefits for society as a whole. This is alluded to in the subtitle of his most famous work, The Fable of The Bees: or, Private Vices, Public Benefits.
In philosophy of mind, the knowledge argument (also known as Mary's Room, Mary the Colour Scientist, or Mary the super-scientist) is a thought experiment proposed by Frank Jackson in his article 'Epiphenomenal Qualia' (1982), and extended in 'What Mary Didn't Know' (1986). The thought experiment describes Mary, a scientist who exists in a black-and-white world where she has extensive access to physical descriptions o
Maxwell's demon is a thought experiment that appears to disprove the second law of thermodynamics. It was proposed by the physicist James Clerk Maxwell in 1867.
Mayfield's Paradox states that to keep everyone out of an information system requires an infinite amount of money, and to get everyone onto an information system also requires infinite money, while costs between these extremes are relatively low. The paradox is depicted as a U-curve, where the cost of a system is on the vertical axis, and the percentage of humanity that can access the system is on the horizontal axis
The metabasis paradox is an instance in the received text of Aristotle's Poetics where, according to many scholars, he makes two incompatible statements. In chapter 13 of the book, Aristotle states that for tragedy to end in misfortune is 'correct,' yet in chapter 14 he judges a type of plot in tragedy 'best' that does not end in misfortune.
Molyneux's problem is a thought experiment in philosophy concerning immediate recovery from blindness. It was first formulated by William Molyneux, and notably referred to in John Locke's An Essay Concerning Human Understanding (1689).
Moore's paradox concerns the apparent absurdity involved in asserting a first-person present-tense sentence such as 'It is raining, but I do not believe that it is raining' or 'It is raining, but I believe that it is not raining.' The first author to note this apparent absurdity was George E. Moore. These 'Moorean' sentences, as they have become known, are paradoxical in that while they appear absurd, they neverthele
Moravec's paradox is the observation that, as Hans Moravec wrote in 1988, 'it is comparatively easy to make computers exhibit adult level performance on intelligence tests or playing checkers, and difficult or impossible to give them the skills of a one-year-old when it comes to perception and mobility'. This counterintuitive pattern may happen because skills that appear effortless to humans, such as recognizing face
A Morton's fork is a type of false dilemma in which contradictory observations lead to the same conclusion. Its name dates back to the rationalising of a benevolence by the 15th century English prelate John Morton.
A movement paradox is a phenomenon of grammar that challenges the transformational approach to syntax. The importance of movement paradoxes is emphasized by those theories of syntax (e.g.
The moving magnet and conductor problem is a famous thought experiment, originating in the 19th century, concerning the intersection of classical electromagnetism and special relativity. In it, the current in a conductor moving with constant velocity, v, with respect to a magnet is calculated in the frame of reference of the magnet and in the frame of reference of the conductor.
The Mpemba effect is the observation that very hot liquids or colloids (such as ice cream) can freeze more quickly than colder ones, for similar volumes and surrounding conditions. Physicists remain divided on the effect's reproducibility, precise definition, and underlying mechanisms.
The navigation paradox states that increased navigational precision may result in increased collision risk. In the case of ships and aircraft, the advent of Global Positioning System (GPS) navigation has enabled craft to follow navigational paths with such greater precision (often of the order of plus or minus 2 m), that, without better distribution of routes, coordination between neighboring craft and collision avoi
Coherence, also called uniformity or consistency, is a criterion for evaluating rules for fair division. Coherence requires that the outcome of a fairness rule is fair not only for the overall problem, but also for each sub-problem.
Newton's cannonball was a thought experiment Isaac Newton used to hypothesize that the force of gravity was universal, and it was the key force for planetary motion. It appeared in his posthumously published 1728 work De mundi systemate (also published in English as A Treatise of the System of the World).
The no–no paradox is a distinctive paradox belonging to the family of the semantic paradoxes (like the Liar paradox). It derives its name from the fact that it consists of two sentences each simply denying what the other says.
The participation criterion is a voting system criterion that says candidates should never lose an election as a result of receiving too many votes in support. More formally, it says that adding more voters who prefer Alice to Bob should not cause Alice to lose the election to Bob.
The no–no paradox is a distinctive paradox belonging to the family of the semantic paradoxes (like the Liar paradox). It derives its name from the fact that it consists of two sentences each simply denying what the other says.
Norton's dome is a thought experiment that exhibits a non-deterministic system within the bounds of Newtonian mechanics. It was devised by John D. Norton in 2003.
The obesity paradox is the finding in some studies of a lower mortality rate for overweight or obese people within certain subpopulations. The paradox has been observed in people with cardiovascular disease and cancer.
In the social sciences, the observer's paradox is a situation in which the phenomenon being observed is unwittingly influenced by the presence of the observer/investigator.
The outcomes paradox (otherwise known as the 'better prognosis hypothesis') is the observation that patients with schizophrenia in developing countries benefit much more from therapy than those in developed countries. This is surprising because the reverse holds for most diseases: 'the richer and more developed the country, the better the patient outcome.' The outcomes paradox came to light in the 1960s due to cross-
In rigid-body dynamics, the Painlevé paradox (also called frictional paroxysms by Jean Jacques Moreau) is the paradox that results from inconsistencies between the contact and Coulomb models of friction. It is named for former French prime minister and mathematician Paul Painlevé.
The paradox of tolerance is a philosophical concept suggesting that if a society extends tolerance to those who are intolerant, it risks enabling the eventual dominance of intolerance, thereby undermining the very principle of tolerance. This paradox was articulated by philosopher Karl Popper in The Open Society and Its Enemies (1945), where he argued that a truly tolerant society must retain the right to deny tolera
The paradox of enrichment is a term from population ecology coined by Michael Rosenzweig in 1971. He described an effect in six predator–prey models where increasing the food available to the prey caused the predator's population to destabilize.
The paradox of fiction, or the paradox of emotional response to fiction, is a philosophical dilemma that questions how people can experience strong emotions to fictional things. The primary question asked is the following: How are people moved by things which do not exist?
The paradox of tolerance is a philosophical concept suggesting that if a society extends tolerance to those who are intolerant, it risks enabling the eventual dominance of intolerance, thereby undermining the very principle of tolerance. This paradox was articulated by philosopher Karl Popper in The Open Society and Its Enemies (1945), where he argued that a truly tolerant society must retain the right to deny tolera
The paradox of hedonism, also called the pleasure paradox, refers to the practical difficulties encountered in the pursuit of pleasure. For the hedonist, constant pleasure-seeking may not yield the most actual pleasure or happiness in the long term when consciously pursuing pleasure interferes with experiencing it.
The paradox of nihilism is a family of paradoxes regarding the philosophical implications of nihilism, particularly situations contesting nihilist perspectives on the nature and extent of subjectivity within a nihilist framework. There are a number of variations of this paradox.
Zeno's paradoxes are a series of philosophical arguments presented by the ancient Greek philosopher Zeno of Elea (c. 490–430 BC), primarily known through the works of Plato, Aristotle, and later commentators like Simplicius of Cilicia.
The paradox of a charge in a gravitational field is an apparent physical paradox in the context of general relativity. A charged particle at rest in a gravitational field, such as on the surface of the Earth, must be supported by a force to prevent it from falling.
Suspense is a state of anxiety or excitement caused by mysteriousness, uncertainty, doubt, or undecidedness. In a narrative work, suspense is the audience's excited anticipation about the plot or conflict (which may be heightened by a violent moment, stressful scene, puzzle, mystery, etc.), particularly as it affects a character for whom the audience feels sympathy.
The Paradox of the Court, also known as the counterdilemma of Euathlus or Protagoras' paradox, is a paradox originating in ancient Greece. The story is related by the Latin author Aulus Gellius in Attic Nights, who says that the famous sophist Protagoras took on a promising pupil, Euathlus, on the understanding that the student pay Protagoras for his instruction after he wins his first court case.
Zeno's paradoxes are a series of philosophical arguments presented by the ancient Greek philosopher Zeno of Elea (c. 490–430 BC), primarily known through the works of Plato, Aristotle, and later commentators like Simplicius of Cilicia.
In aquatic biology, the paradox of the plankton describes the situation in which a limited range of resources supports an unexpectedly wide range of plankton species, apparently flouting the competitive exclusion principle, which holds that when two species compete for the same resource, one will be driven to extinction.
The paradox of tolerance is a philosophical concept suggesting that if a society extends tolerance to those who are intolerant, it risks enabling the eventual dominance of intolerance, thereby undermining the very principle of tolerance. This paradox was articulated by philosopher Karl Popper in The Open Society and Its Enemies (1945), where he argued that a truly tolerant society must retain the right to deny tolera
The paradox of value, also known as the diamond–water paradox, is the paradox that, although water is on the whole more useful in terms of survival than diamonds, diamonds command a higher price in the market. The philosopher Adam Smith is often considered to be the classic presenter of this paradox, although it had already appeared as early as Plato's Euthydemus.
Paradoxical laughter is an exaggerated expression of humour which is unwarranted by external events. It may be uncontrollable laughter which may be recognised as inappropriate by the person involved.
A perceptual paradox illustrates the failure of a theoretical prediction. Theories of perception are supposed to help a researcher predict what will be perceived when senses are stimulated.
A performative contradiction (German: performativer Widerspruch) arises when the making of an utterance rests on necessary presuppositions that contradict the proposition asserted in the utterance. The term was coined by Jürgen Habermas and Karl-Otto Apel, who attribute the first elaboration of the concept to Jaakko Hintikka, in his analysis of Descartes' cogito ergo sum argument.
In philosophy of mind, a philosophical zombie (or 'p-zombie') is a being in a thought experiment that is physically identical to a normal human being but does not have conscious experience. For example, if a philosophical zombie were poked with a sharp object, it would not feel any pain, but it would react exactly the way any conscious human would.
Philosophy of mind is a branch of philosophy that deals with the nature of the mind and its relation to the body and the external world. The mind–body problem is a paradigmatic issue in philosophy of mind, although a number of other issues are addressed, such as the hard problem of consciousness and the nature of particular mental states.
A physical paradox is an apparent contradiction in physical descriptions of the universe. While multiple physical paradoxes have accepted resolutions, others defy resolution and may indicate flaws in theory.
Vote-ratio, weight-ratio, or population-ratio monotonicity is a property of some apportionment methods. It says that if the entitlement for A {\\displaystyle A} grows at a faster rate than B {\\displaystyle B} (i.e.
Postdiction involves explanation after the fact. In skepticism, it is considered an effect of hindsight bias that explains claimed predictions of significant events such as plane crashes and natural disasters.
The potato paradox is a mathematical calculation that has a result which seems counterintuitive to many people. The Universal Book of Mathematics states the problem as such: Fred brings home 100 kg of potatoes, which (being purely mathematical potatoes) consist of 99% water.
The preface paradox, or the paradox of the preface, was introduced by David Makinson in 1965. Similar to the lottery paradox, it presents an argument according to which it can be rational to accept mutually incompatible beliefs.
The preparedness paradox is the proposition that if a society or individual acts effectively to mitigate a potential disaster such as a pandemic, natural disaster or other catastrophe so that it causes less harm, the avoided danger will be perceived as having been much less serious because of the limited damage actually caused. The paradox is the incorrect perception that there had been no need for careful preparatio
The prevention paradox describes the situation where the majority of cases of a disease come from a population at low or moderate risk of that disease, and only a minority of cases come from the high risk population (of the same disease). This is because the number of people at high risk is small.
The problem of evil, also known as the problem of suffering, is the philosophical question of how to reconcile the existence of evil and suffering with an omnipotent, omnibenevolent, and omniscient God. There are currently differing definitions of these concepts.
The productivity paradox refers to the slowdown in productivity growth in the United States in the 1970s and 1980s despite rapid development in the field of information technology (IT) over the same period. The term was coined by Erik Brynjolfsson in a 1993 paper ('The Productivity Paradox of IT') inspired by a quip by Nobel Laureate Robert Solow 'You can see the computer age everywhere but in the productivity statis
Pulsus paradoxus, also paradoxic pulse or paradoxical pulse, is an abnormally large decrease in stroke volume, systolic blood pressure (a drop more than 10 mmHg) and pulse wave amplitude during inspiration. Pulsus paradoxus is not related to pulse rate or heart rate, and it is not a paradoxical rise in systolic pressure.
Reflexive monism is a philosophical position developed by Max Velmans, in his books Understanding Consciousness (2000, 2009) and Toward a Deeper Understanding of Consciousness (2017), to address the problems of consciousness. It is a modern version of an ancient view that the basic stuff of the universe manifests itself both physically and as conscious experience (a dual-aspect theory in the traditions of Spinoza and
Roko's basilisk is a thought experiment which states that there could be an artificial superintelligence in the future that, while otherwise benevolent, would punish anyone who knew of its potential existence but did not directly contribute to its advancement or development, in order to incentivize that advancement. It originated in a 2010 post at discussion board LessWrong, a rationalist community web forum.
The sad clown paradox is the contradictory association, in performers, between comedy and mental disorders such as depression and anxiety. For those affected, early life is characterised by feelings of deprivation and isolation, where comedy evolves as a release for tension, removing feelings of suppressed physical rage through a verbal outlet.
Sayre's paradox is a dilemma encountered in the design of automated handwriting recognition systems. A standard statement of the paradox is that a cursively written word cannot be recognized without being segmented and cannot be segmented without being recognized.
Scenario testing is a software testing activity that uses scenarios: hypothetical stories to help the tester work through a complex problem or test system. The ideal scenario test is a credible, complex, compelling or motivating story; the outcome of which is easy to evaluate.
The service recovery paradox (SRP) is a situation in which a customer thinks more highly of a company after the company has corrected a problem with their service, compared to how they would regard the company if non-faulty service had been provided. The main reason behind this thinking is that successful recovery of a faulty service increases the assurance and confidence from the customer.
The Sherman paradox was a term used to describe the anomalous pattern of inheritance found in fragile X syndrome. The phenomenon is also referred to as anticipation or dynamic mutation.
Sleep debt or sleep deficit is the cumulative effect of not getting enough sleep. A large sleep debt may lead to mental or physical fatigue, and can adversely affect one's mood, energy, and ability to think clearly.
Solomon's paradox is the observation that people can give reasonable advice to others, but fail to apply this advice to their own situation.
The St. Petersburg paradox or St.
A status paradox can be one of several paradoxes involving 'status', in the meaning of either medical state or social status.
In general relativity, the sticky bead argument is a simple thought experiment designed to show that gravitational radiation is indeed predicted by general relativity and can have physical effects. These claims were not widely accepted prior to about 1955, but after the introduction of the bead argument, any remaining doubts soon disappeared from the research literature.
James Bond Stockdale (December 23, 1923 – July 5, 2005) was a U.S. Navy vice admiral, aviator, and Stoic philosopher who received the Medal of Honor in 1976 for his leadership as a POW for more than seven years during the Vietnam War. Stockdale was the most senior naval officer held captive in Hanoi, North Vietnam.
In the science of fluid flow, Stokes' paradox is the phenomenon that there can be no creeping flow of a fluid around a disk in two dimensions; or, equivalently, the fact there is no non-trivial steady-state solution for the Stokes equations around an infinitely long cylinder. This is opposed to the 3-dimensional case, where Stokes' method provides a solution to the problem of flow around a sphere.
The Taeuber Paradox is a paradox in demography, which results from two seemingly contradictory expectations given a population-wide decrease in mortality, e.g. from curing or reducing the mortality of a disease in a population.
John Alan Feduccia (born April 25, 1943) is a paleornithologist specializing in the origins and phylogeny of birds. He is S. K. Heninger Distinguished Professor Emeritus at the University of North Carolina.
The Antitrust Paradox is an influential 1978 book by Robert Bork that criticized the state of United States antitrust law in the 1970s. A second edition, updated to reflect substantial changes in the law, was published in 1993.
Zeno's paradoxes are a series of philosophical arguments presented by the ancient Greek philosopher Zeno of Elea (c. 490–430 BC), primarily known through the works of Plato, Aristotle, and later commentators like Simplicius of Cilicia.
The survival lottery is a thought experiment, proposed by the philosopher John Harris. The basis of the idea is to ask people to imagine if organ donation were expected to save more individuals than it would kill.
Thomson's lamp is a philosophical thought experiment based on infinites. It was devised in 1954 by British philosopher James F. Thomson, who used it to analyze the possibility of a supertask, which is the completion of an infinite number of tasks.
A Gabriel's horn (also called Torricelli's trumpet) is a type of geometric figure that has infinite surface area but finite volume. The name refers to the Christian idea that the archangel Gabriel will one day blow his horn to announce Judgment Day.
The transparent eyeball is a philosophical metaphor originated by American transcendentalist philosopher Ralph Waldo Emerson. In his essay Nature, the metaphor stands for a view of life that is absorbent rather than reflective, and therefore takes in all that nature has to offer without bias or contradiction.
The two capacitor paradox or capacitor paradox is a paradox, or counterintuitive thought experiment, in electric circuit theory. The thought experiment is usually described as follows: Two identical capacitors are connected in parallel with an open switch between them.
In computing, the Two Generals' Problem (or Chinese Generals Problem) is a thought experiment meant to illustrate the pitfalls and design challenges of attempting to coordinate an action by communicating over an unreliable link. In the experiment, two generals are only able to communicate with one another by sending a messenger through enemy territory.
The tzimtzum or tsimtsum (Hebrew: צִמְצוּם, romanized: ṣimṣum, lit. 'contraction, constriction, condensation') is a term used in Lurianic Kabbalah to explain Isaac Luria's doctrine that God began the process of creation by limiting the Ohr Ein Sof (infinite light) of the Godhead in order to allow for a conceptual space in which the Four Worlds, or finite realms, could exist. This primordial initial contraction, formi
Upstream contamination by floating particles is a counterintuitive phenomenon in fluid dynamics. When pouring water from a higher container to a lower one, particles floating in the latter can climb upstream into the upper container.
Washburn's paradox, Washburn's fallacy or the genetic similarity fallacy is a statement about the genetic relatedness of individuals that is relevant in Hamilton's rule. It is named for American anthropologist Sherwood Washburn, who discussed the issue in his critique of sociobiology and kin selection.
The Will Rogers phenomenon, also rarely called the Okie paradox, is when moving an observation from one group to another increases the average of both groups. It is named after a joke attributed to the comedian Will Rogers about Dust Bowl migration during the Great Depression: When the Okies left Oklahoma and moved to California, they raised the average intelligence level in both states.
The willpower paradox is the idea that people may do things better by focusing less directly on doing them, implying that the direct exertion of volition may not always be the most powerful way to accomplish a goal. Research suggests that intrapersonal communication (talking to oneself) and maintaining a questioning mind are more likely to bring change.
Zeno of Elea (; Ancient Greek: Ζήνων ὁ Ἐλεᾱ́της; c. 490 – c. 430 BC) was a pre-Socratic Greek philosopher from Elea, in Southern Italy (Magna Graecia). He was a student of Parmenides and one of the Eleatics.
Zeno's paradoxes are a series of philosophical arguments presented by the ancient Greek philosopher Zeno of Elea (c. 490–430 BC), primarily known through the works of Plato, Aristotle, and later commentators like Simplicius of Cilicia.
Zeno's paradoxes are a series of philosophical arguments presented by the ancient Greek philosopher Zeno of Elea (c. 490–430 BC), primarily known through the works of Plato, Aristotle, and later commentators like Simplicius of Cilicia.