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[[folder:Toupee Fallacy]]

The Toupee Fallacy is when a debater claims that all examples of a subject conform to a specific quality because they've never seen one that hadn't, ignoring that any examples they ''did'' see that didn't have that quality they didn't recognize as examples.

Consider this statement: "Every toupee is a DodgyToupee. I know because I've never seen one that looked real." Naturally, if the speaker ''did'' see a toupee that looked real, they would simply assume it was actual hair - that is, after all, what a toupee is ''meant to do''.

The Toupee Fallacy comes up most often in the discussion of transgender individuals; a person will claim (to use one example) they've never seen a transgender woman that didn't obviously look like a man in a dress. Of course, they've likely seen dozens, but simply assumed they were biologically female.
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It's useful to visualize the type of medieval castle for which the fallacy is named. The bailey (weak argument) is a lightly fortified field containing useful and valuable things like smithies and stables. The motte is a heavily fortified tower upon a kill. The lord and his men would defend the bailey if they could, but would retreat into the motte if things got hairy. And when the attackers left, they would go back down into the bailey and restore that. In the same way, a person can switch between arguments. It's something of a reverse form of the strawman fallacy, where rather than misrepresenting their opponent with a weak argument, the arguer (temporarily) replaces their own argument with a stronger one.

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It's useful to visualize the type of medieval castle for which the fallacy is named. The bailey (weak argument) is a lightly fortified field containing useful and valuable things like smithies and stables. The motte is a heavily fortified tower upon on a kill.hill. The lord and his men would defend the bailey if they could, but would retreat into the motte if things got hairy. And when the attackers left, they would go back down into the bailey and restore that. In the same way, a person can switch between arguments. It's something of a reverse form of the strawman fallacy, where rather than misrepresenting their opponent with a weak argument, the arguer (temporarily) replaces their own argument with a stronger one.


It's useful to visualize the type of medieval castle for which the fallacy is named. The bailey (weak argument) is a lightly fortified field containing useful and valuable things like smithies and stables. The motte is a heavily fortified tower upon a kill. The lord and his mend would defend the bailey if they could, but would retreat into the motte if things got hairy. And when the attackers left, they would go back down into the bailey and restore that. In the same way, a person can switch between arguments. It's something of a reverse form of the strawman fallacy, where rather than misrepresenting their opponent with a weak argument, the arguer (temporarily) replaces their own argument with a stronger one.

to:

It's useful to visualize the type of medieval castle for which the fallacy is named. The bailey (weak argument) is a lightly fortified field containing useful and valuable things like smithies and stables. The motte is a heavily fortified tower upon a kill. The lord and his mend men would defend the bailey if they could, but would retreat into the motte if things got hairy. And when the attackers left, they would go back down into the bailey and restore that. In the same way, a person can switch between arguments. It's something of a reverse form of the strawman fallacy, where rather than misrepresenting their opponent with a weak argument, the arguer (temporarily) replaces their own argument with a stronger one.


However, [[StrawNihilist people who assume]] that such actions were [[HumansAreBastards the result of human nature that is present in all human beings]], tend to forget about those other kinds of people who actively try to help people in need (or at least support those, but cannot do much about it). These characters would assume that such actions are reflective of the entire human race, making flimsy claims of many people who do help only do so out of {{Pride}} and publicity ([[TruthInTelevision while there are some who do that]], there are also much more people who genuinely want to help) and that ideas of hatred, prejudice and self-destruction are inherent in ''[[AlwaysChaoticEvil all human beings.]]'' They all reject claims of RousseauWasRight and the idea of a Blank Slate, replacing them with HumansAreBastards (or [[HumansAreTheRealMonsters the real monsters in certain cases]]). Sometimes, they would deny that they share those aspects with humanity, [[PsychologicalProjection claiming that their suffering was of the actions of humanity]] (when it could be [[{{Hypocrite their own fault]]) or embrace that they're part of humanity and use that as an excuse for their actions.

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However, [[StrawNihilist people who assume]] that such actions were [[HumansAreBastards the result of human nature that is present in all human beings]], tend to forget about those other kinds of people who actively try to help people in need (or at least support those, but cannot do much about it). These characters would assume that such actions are reflective of the entire human race, making flimsy claims of many people who do help only do so out of {{Pride}} and publicity ([[TruthInTelevision while there are some who do that]], there are also much more people who genuinely want to help) and that ideas of hatred, prejudice and self-destruction are inherent in ''[[AlwaysChaoticEvil all human beings.]]'' They all reject claims of RousseauWasRight and the idea of a Blank Slate, replacing them with HumansAreBastards (or [[HumansAreTheRealMonsters the real monsters in certain cases]]). Sometimes, they would deny that they share those aspects with humanity, [[PsychologicalProjection claiming that their suffering was of the actions of humanity]] (when it could be [[{{Hypocrite [[{{Hypocrite}} their own fault]]) or embrace that they're part of humanity and use that as an excuse for their actions.


This is similar to the valid ''reductio ad absurdum'' argument, which attempts to disprove a statement by assuming it to be true and showing how that leads to a contradiction. "Quantum physics has proven than reality does not exist objectively" would be a strong argument that (some aspect of) quantum physics is ''bad science'', but even if it were true it could never prove that reality is not objective.

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This is similar to the valid ''reductio ad absurdum'' argument, which attempts to disprove a statement by assuming it to be true and showing how that leads to a contradiction. "Quantum physics has proven than that reality does not exist objectively" would be a strong argument that (some aspect of) quantum physics is ''bad science'', but even if it were true it could never prove that reality is not objective.

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[[folder:Motte and Bailey]]
Switching a hard to defend position for a more easily defended (but superficially similar) one when the former position is challenged.

It's useful to visualize the type of medieval castle for which the fallacy is named. The bailey (weak argument) is a lightly fortified field containing useful and valuable things like smithies and stables. The motte is a heavily fortified tower upon a kill. The lord and his mend would defend the bailey if they could, but would retreat into the motte if things got hairy. And when the attackers left, they would go back down into the bailey and restore that. In the same way, a person can switch between arguments. It's something of a reverse form of the strawman fallacy, where rather than misrepresenting their opponent with a weak argument, the arguer (temporarily) replaces their own argument with a stronger one.

For example: let's say a faculty member at a school says that building a new expensive science building would improve student performance. Another faculty member counters that most of the money would be better spent hiring better science teachers and starting new student support programs. The former faculty member says "look, all I'm saying is we need to update those old classrooms." The problem is that they weren't originally saying that, they had a specific proposal, and, when that proposal was attacked, made it seem like they were just raising awareness for the issue.
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->If my car was Ferrari, it would be able to travel at over a hundred miles per hour.\\

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->If my car was a Ferrari, it would be able to travel at over a hundred miles per hour.\\



As a rebuttal, [[DeadpanSnarker one might]] [[HypocriticalHumour simply point out]] that they met a man on the way home who said that anecdotal evidence doesn't prove anything.

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As a rebuttal, [[DeadpanSnarker one might]] one]] might [[HypocriticalHumour simply point out]] that they met a man on the way home who said that anecdotal evidence doesn't prove anything.



There are also times this argument is valid, such as when there are what economists call [[http://en.wikipedia.org/wiki/Network_effect network effects]]. In brief, if the value of a good or service changes based on the number of users, then pointing out the number of using it could be valid. For example, when telephones were adopted, their value increased with every new telephone added to the network. If business software is used by many companies, being ubiquitous is a selling point. If no one else uses an instant messenger, it's useless, but if everyone uses it, it's more valuable to the end user. If all of one's friends use a specific social networking site and you want to use social media, it makes sense to follow your friends. If a cell phone company allows unlimited calls between two members of their networks, the number of clients they have and their demographics are both legitimate concerns. If most counties and companies are using a particular shipping container, rail-road gauge, or standard of measure, there's good reasons to adopt the same standards.

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There are also times this argument is valid, such as when there are what economists call [[http://en.wikipedia.org/wiki/Network_effect network effects]]. In brief, if the value of a good or service changes based on the number of users, then pointing out the number of people using it could be valid. For example, when telephones were adopted, their value increased with every new telephone added to the network. If business software is used by many companies, being ubiquitous is a selling point. If no one else uses an instant messenger, it's useless, but if everyone uses it, it's more valuable to the end user. If all of one's friends use a specific social networking site and you want to use social media, it makes sense to follow your friends. If a cell phone company allows unlimited calls between two members of their networks, the number of clients they have and their demographics are both legitimate concerns. If most counties and companies are using a particular shipping container, rail-road gauge, or standard of measure, there's good reasons to adopt the same standards.standards.

However, what makes these situations different from the Bandwagon Fallacy is that in these cases, it's clear why there's a bandwagon, and why getting on it is a good idea. With the Bandwagon Fallacy, however, no such reason is made clear.



The term was coined by Creator/CSLewis in an essay of the same name in which he describes the (fictional) origin of the fallacy: a boy named Ezekiel Bulver heard his parents arguing when his mother said "Oh, you say that because you are a man." at which point Bulver realized that "refutation is no necessary part of argument".

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The term was coined by Creator/CSLewis in an essay of the same name in which he describes the (fictional) origin of the fallacy: a boy named Ezekiel Bulver heard his parents arguing when his mother said said, "Oh, you say that because you are a man." at which point Bulver realized that "refutation is no necessary part of argument".



Another excellent example of how a [[RightForTheWrongReasons false argument is combined with a true conclusion]]: in medicine, pressure around the brain can cause severe headaches. Ancient surgeons assumed that it must be demons in the patient's head causing the pain, and that exposing them to light would kill them or drive them out; therefore, they drilled holes in the patient's skull. The end result relieved the pressure and actually ''did'' cure the headaches, even though their reasoning was entirely faulty.

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Another excellent example of how a [[RightForTheWrongReasons false argument is combined with a true conclusion]]: in medicine, pressure around the brain can cause severe headaches. Ancient surgeons assumed that it must be demons in the patient's head causing the pain, and that [[WeakenedByTheLight exposing them to light would kill them or drive them out; out]]; therefore, they drilled holes in the patient's skull. The end result relieved the pressure and actually ''did'' cure the headaches, even though their reasoning was entirely faulty.



However, [[StrawNihilist people who assume]] that such actions were [[HumansAreBastards the result of human nature that is present in all human beings]], tend to forget about those other kinds of people who actively try to help people in need (or at least support those, but cannot do much about it). These characters would assume that such actions are reflective of the entire human race, making flimsy claims of many people who do help only do so out of {{Pride}} and publicity ([[TruthInTelevision while there are some who do that]], there are also much more people who genuinely want to help) and that ideas of hatred, prejudice and self-destruction are inherent in ''all human beings.'' They all reject claims of RousseauWasRight and the idea of a Blank Slate, replacing them with HumansAreBastards (or [[HumansAreTheRealMonsters the real monsters in certain cases]]). Sometimes, they would deny that they share those aspects with humanity, [[PsychologicalProjection claiming that their suffering was of the actions of humanity]] [[{{Hypocrite}} (when it could be their own fault)]] or embrace that they're part of humanity and using that as an excuse for their actions.

More blatant examples include dismissing the victims of such atrocities as being just as bad as the perpetrators, including children as part of their perceived Human Nature and igniting a [[DomesticAbuse Family Feud]] between family members, just because they perceive them as [[HumansAreBastards bastards]] deep down, no matter how they treated them.

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However, [[StrawNihilist people who assume]] that such actions were [[HumansAreBastards the result of human nature that is present in all human beings]], tend to forget about those other kinds of people who actively try to help people in need (or at least support those, but cannot do much about it). These characters would assume that such actions are reflective of the entire human race, making flimsy claims of many people who do help only do so out of {{Pride}} and publicity ([[TruthInTelevision while there are some who do that]], there are also much more people who genuinely want to help) and that ideas of hatred, prejudice and self-destruction are inherent in ''all ''[[AlwaysChaoticEvil all human beings.'' ]]'' They all reject claims of RousseauWasRight and the idea of a Blank Slate, replacing them with HumansAreBastards (or [[HumansAreTheRealMonsters the real monsters in certain cases]]). Sometimes, they would deny that they share those aspects with humanity, [[PsychologicalProjection claiming that their suffering was of the actions of humanity]] [[{{Hypocrite}} (when it could be [[{{Hypocrite their own fault)]] fault]]) or embrace that they're part of humanity and using use that as an excuse for their actions.

More blatant examples include dismissing the victims of such atrocities as being just as bad as the perpetrators, [[EnfantTerrible including children children]] as part of their perceived Human Nature and igniting a [[DomesticAbuse Family Feud]] between family members, just because they perceive them as [[HumansAreBastards bastards]] deep down, no matter how they treated them.



Besides a word's definition, most words have a connotation that implies that its subject is either good or bad. For example, both the words "cabin" and "shack" mean basically the same thing, but one word has a positive connotation and the other has a negative connotation. Using a loaded term by itself isn't fallacious, but using loaded terms as a basis for an argument is. Using a loaded term to imply that the subject in question is bad when the point of your argument is that it's bad is also another form of Begging the Question.

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Besides a word's definition, most words have a connotation that implies that its subject is either good or bad. For example, both the words "cabin" and "shack" mean basically the same thing, but one word has a positive (or at least neutral) connotation and the other has a negative connotation. Using a loaded term by itself isn't fallacious, but using loaded terms as a basis for an argument is. Using a loaded term to imply that the subject in question is bad when the point of your argument is that it's bad is also another form of Begging the Question. Not to be confused with Administrivia/LoadedTropeWord, which is when a word has a double meaning on this website.



A fallacy in which one or more of the concepts (or premises) on which an argument depends are (usually implicitly) denied by the argument itself, thus meaning the arguer is taking two or more opposed positions at the same time. [[TropeNamer Named]] by Creator/AynRand (and discussed in more detail [[UsefulNotes/{{Objectivism}} here]]). Popular in anti-science literature where scientific processes will be used in an attempt to discredit their own underlying assumptions.

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A fallacy in which one or more of the concepts (or premises) on which an argument depends are (usually implicitly) denied by the argument itself, thus meaning the arguer is taking two or more opposed positions at the same time. [[TropeNamer Named]] by Creator/AynRand (and discussed in more detail [[UsefulNotes/{{Objectivism}} here]]). Popular in anti-science [[ScienceIsBad anti-science]] literature where scientific processes will be used in an attempt to discredit their own underlying assumptions.


Wiki/TheOtherWiki expresses Bulverism as:

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Wiki/TheOtherWiki Website/TheOtherWiki expresses Bulverism as:


It's said that "'Dog Bites Man' is not news; 'Man Bites Dog' is news." Using that example, this trope is when somebody assumes that men biting dogs is more common than the reverse, because it appears in the papers more often.

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It's said that "'Dog Bites Man' is not news; 'Man Bites Dog' is news." Using that example, this trope fallacy is when somebody assumes that men biting dogs is more common than the reverse, because it appears in the papers more often.


This idea is rarely treated as a necessary worldwide view in fiction, but when it does happen, there is a high chance of TooBleakStoppedCaring or TastesLikeDiabetes and accusations of the Author expressing this view.

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This idea is rarely treated as a necessary worldwide view in fiction, but when it does happen, there is a high chance of TooBleakStoppedCaring or TastesLikeDiabetes SweetnessAversion and accusations of the Author expressing this view.

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This is similar to the valid ''reductio ad absurdum'' argument, which attempts to disprove a statement by assuming it to be true and showing how that leads to a contradiction. "Quantum physics has proven than reality does not exist objectively" would be a strong argument that (some aspect of) quantum physics is ''bad science'', but even if it were true it could never prove that reality is not objective.


There are many people in the world who would be considered as bad [[Administrivia/RuleOfCautiousEditingJudgement (at least in the views of some people)]] and would be seen as the "worst humanity has to offer". However, there are also just as many people who actively try to help whoever they can and to try to make the world a better place, [[KnightInSourArmor even if they see the worst aspects of such.]]

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There are many people in the world who would be considered as bad [[Administrivia/RuleOfCautiousEditingJudgement (at least in the views of some people)]] and would be seen as the "worst humanity has to offer". However, there are also just as many people who actively try to help whoever they can and to try to make the world a better place, [[KnightInSourArmor even if they see the worst aspects of such.]]

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[[folder:Process of Elimination Fallacy]]
Also called:
* ''Arcane Explanation''
* ''Holmesian Fallacy''
* ''Sherlock Holmes Fallacy''

This fallacy happens when an explanation is considered "correct" after other alternative explanations have been ruled out. It is named for the quote by Franchise/SherlockHolmes from various stories where he says that when one eliminates all which is impossible, whatever is left is the truth no matter how improbable.

For this maxim to work, that means one has to find all possible explanations and eliminate them one by one. This however requires omniscience, can lead to [[InsaneTrollLogic very improbable explanations]] and the real answer may be one that was never considered. If the science behind the right or wrong explanation wasn't known at the time (such as [[ClarkesThirdLaw being considered magic or of the gods]]), see ScienceMarchesOn.
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This fallacy occurs when the middle term of a standard three-step syllogism is not distributed in either premise. [[https://static.tvtropes.org/pmwiki/pub/images/3912.jpg This picture]] is a case of undistributed middle. Using that image, "black and white" is the middle term, the term that appears in both premises; it is undistributed because neither premise refers to ''all'' things that are "black and white". Newspapers are black and white as well, and they are neither penguins nor old TV shows. "Things that are black and white" is the superset, and it contains many subsets that do not overlap at all. In casual use, undistributed middle can be hard to spot.

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This fallacy occurs when the middle term of a standard three-step syllogism is not distributed[[note]] a distributed premise is one that gives you information on at least one entire class of things, eg. "all penguins are birds", but not "some birds are penguins" - consult logic textbooks[[/note]] in either premise. [[https://static.tvtropes.org/pmwiki/pub/images/3912.jpg This picture]] is a case of undistributed middle. Using that image, "black and white" is the middle term, the term that appears in both premises; it is undistributed because neither premise refers to ''all'' things that are "black and white". Newspapers are black and white as well, and they are neither penguins nor old TV shows. "Things that are black and white" is the superset, and it contains many subsets that do not overlap at all. In casual use, undistributed middle can be hard to spot.


"Begging the question" is often used colloquially to mean "raising the question". (Example: "With the rise of online media, this begs the question: do public libraries have a future?") This usage is a common BerserkButton for academics aware of the original meaning. It doesn't help that the original phrase was first translated from Greek into Latin, and from Latin into English, resulting in the confusing phrase, "Begging the question," which is incomprehensible to English speakers (there being no begging nor question involved) unless one already knows the dialectical context.

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"Begging the question" is often used colloquially to mean "raising the question". (Example: "With the rise of online media, this begs the question: do public libraries have a future?") This usage is a common BerserkButton for academics aware of the original meaning. It doesn't help that the original phrase was first translated from Greek into Latin, and from Latin into English, resulting in the confusing phrase, "Begging the question," which is incomprehensible to English speakers (there being no begging nor question involved) unless one is already knows the dialectical context.aware of its meaning.

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