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Logical fallacy

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We reason from our bedrock beliefs, not to them. Infanticide and slavery are not forbidden in our society because the arguments against these practices are stronger than the arguments in favor of them, but because the practices revolt us. We would not listen to anyone who cared to make arguments in favor of them.
—Judge Richard Posner, Overcoming Law (technically an Appeal to Digust, showing why pure logic is best left to Vulcans).

A logical fallacy is an error in the logic of an argument [1][2] that prevents it from being logically valid but does not prevent it from swaying people's minds. Nor does it necessarily mean the conclusion is false, only that the invalid argument does not support it.

Logical fallacies come from human intuition. A logical fallacy is not necessarily a Bayesian fallacy [3], so given a particular circumstance, jumping to the conclusion will be more likely than not, and get baked into human thinking as a heuristic [4]. When the heuristic is applied outside its reasonable bounds, it becomes a cognitive bias.

The problem is that this can lead to you being grievously wrong about reality [5]. So you may form an opinion by a heuristic (System 1 thinking), but you need to show your working to make sure you haven't just said something silly (System 2 thinking).

This particularly applies to thinking about science, because scientific thinking is unintuitive for most people unless trained into it; and to arguing your points in general, because heuristics are full of glaring exceptions.

Explanation[edit]

See the main article on this topic: Syllogism

Must be used in argument[edit]

One common error when first learning about logical fallacies is to fail to realise that a fallacy can only be present if it is used as part of an argument [6]. For example, "So-and-so is a socialist" is not an ad hominem fallacy (see below) because it is simply a statement. So-and-so may be a socialist. "So-and-so is a socialist, therefore s/he is wrong" is an ad hominem because a conclusion is being drawn, and the conclusion has nothing to do with the premise. It attacks the opponent; not the opponent's argument. This can be more complicated than it sounds, however, because the conclusion that s/he is wrong is often implied.

Likewise, "You are an idiot" is merely an assertion. Further, "you are saying idiotic things, therefore you are an idiot" may be a valid argument regardless of whether the premise (the opponent is saying idiotic things) is true. However, it is only a sound argument in the event the premise is true, and if "saying idiotic things" makes one an idiot. (Even geniuses have said idiotic things. Just ask their spouses.)

Validity versus truth[edit]

Just because an argument is valid does not mean the conclusion is true. A valid argument simply means that if the premises are true, the conclusion must be true as well. A sound argument is a valid argument with the additional requirement that the premises (and thus the conclusion) are true [7]. For instance, consider the following argument.

P1: All humans are cows.
P2: All cows are plants.
C1: All humans are plants.

Although the conclusion is false and the premises are false, this is still a valid argument because if the premises were true, the conclusion must be true as well. Since at least one premise is false, the argument is valid but not sound [8].

Fallacy-dropping[edit]

What we have here is a blatant example of argument by assertion. It's therefore clear your mother was a whore, and you flunked out of elementary school. </every_pretentious_redditor_ever>
—Colonel Custer[9]

It is not acceptable to merely state that one's opponent is using a fallacy (as above). One must explain how the opponent's argument is fallacious (eg, they claim that you are a shill), why it is wrong (there's no evidence that you are a paid government disinformation agent), and what that means for their argument (if you're not a shill, then your arguments can't be hand waved away) [10].

This need not be a drawn-out paragraph. Even "your ad hominem is irrelevant to my argument, so my argument stands" is sufficient.

Otherwise, one runs into the risk of fallacy dropping -- claiming someone's argument is wrong without bothering to explain why -- which comes dangerously close to ad hominem. (It's equivalent to shouting "your logic is bad!" and claiming victory.)

Reductio ad absurdum[edit]

One of the techniques that is often used to expose fallacies is reductio ad absurdum. When using this technique, one attempts to disprove the premises of an argument by showing that it leads to ridiculous, absurd, or impractical conclusions. The classic argument against omnipotence that argues “Can an omnipotent God create a stone he cannot lift?” can be thought of as an example of this.[11] Christians and some philosophers have been trying to solve that one since at least the 12th century with limited success. For example, Christians may argue that God cannot do things that defy the rules of logic, which implies that logic is more powerful than God thus refuting his omnipotence. Or they will argue that God can do things which are illogical because he is God, though that is a bit self-contradictory as the Christian God is logic. But we digress.

The exact details of how to use reductio ad absurdum is complex, so we shall refer you to the Internet Encylopedia or the page on reductio ad absurdum instead of trying to recap it here. A good example of reductio ad absurdum in action is the page on the flat earth model of the world which shows the absurdities that arise when one takes the flat earth model of the earth seriously which some people still do.

Types[edit]

There is not a consensus among philosophers about how to best organize fallacies. They can be classified as inductive and deductive, formal and informal, categories pertaining to the psychological factors that led people to create them, and the epistemological or logical factors that underlie them.[12] Another problem that occurs when organizing fallacies is that many of them can be placed in different areas. Consider, for example, the equality fallacy. It is a fallacy of ambiguity as it is not often clear what people mean when they say one should be treated “equally”. It is a political correctness fallacy as liberal politicians advocate for the idea that one should be offended if people are not treated “equally”. It is a jumping to conclusions fallacy as it assumes that the blind should be treated "equally" to someone who has 20/20 vision (which is clearly a logical error if you work at the DMV or are responsible for hiring referees). It is an appeal to self-evident truth fallacy as the founding fathers of the USA claimed that “all men are created equal” is a self-evident truth even though it is quite clear that all men are not created equal as some men are smarter than others, stronger than others, taller than others, etc. It is also a loaded language fallacy as the term is imbued with emotional connotations. It is also a conditional fallacy as there are logical ways to use the word equality such as the right to be equally judged by the law. And if you doubt that the promotion of equality is a fallacy, then you probably don’t know about how laws that promote equality in the USA, namely the 1964 Civil Rights Act and the Equal Employment Opportunity Act of 1972, have led to the prison rape of women by male guards.[13][14][15] But we digress.

Due to the difficulties organizing fallacies, often times sites will simply list the fallacies alphabetically and avoid attempting to organize them. While this works on some level, it is often not very helpful when trying to understand fallacies as there are a lot of them. People need to have some sort of schema in order to understand them and for this reason this page has decided to organize them for you. The primary division of fallacies utilized is formal and informal. A Formal fallacy is an argument in which the conclusion would not necessarily be true whether or not its premises are correct, because it does not follow valid logical structure. An Informal fallacy, on the other hand, is contingent on the argument's content or possibly the motive of the arguer. Within the informal category, the page has further subdivided the fallacies into fallacies of presumption, fallacies of relevance, and fallacies of clarity. This is a way of categorizing fallacies mentioned by the Internet Encyclopedia of Philosophy[12], is used elsewhere such as at wiki-university, and is one of the more common ways of organizing fallacies. Another site that was used as a guide for organizing fallacies was Fallacy Files. In addition to the formal and informal fallacy sections, this page has added a section for conditional fallacies, which are broader categories that have both a non-fallacious and a fallacious component, and a section for argumentative fallacies, which are fallacious ways of presenting information that incorporate informal fallacies. While this list is quite extensive, it is not comprehensive as there are subfallacies or fallacies that pertain to specific fields of study that may not have been mentioned.

Formal[edit]

See the main article on this topic: Formal fallacy

All formal fallacies are forms of invalid reasoning and specific types of non-sequitur.[12]

Syllogistic fallacy[edit]

Any instance in which a syllogism with incorrect structure is used.[16][17]

  1. Four-term fallacy: Any syllogism in which four terms are present, instead of the mandatory three.[16][18]
    1. Ambiguous Middle Term: Using an ambiguous term in a premise of a logical syllogism.[16][12]
  2. Enthymeme: When an unstated premise is necessary for logical validity.
  3. Negative conclusion from affirmative premises: Asserting some negative fact from positive premises.[16][18]
  4. Affirmative conclusion from a negative premise: Asserting some positive fact from negative premises.[16][18][17]
  5. Fallacy of Exclusive Premises (also known as two Negative Premises): a categorical syllogism that is invalid because both of its premises are negative.[16][18]
  6. Illicit process: Incorrectly concluding for all of a set when the premises apply to only some of a set. Specificially, the illicit major and illicit minor.[16]
    1. Illicit Major: All A are B. No C are A. Therefore, no C are B.[16][18]
    2. Illicit Minor: All A are B. All A are C. Therefore, all C are B.[16][18]
  7. Undistributed Middle: the middle term in a categorical syllogism is not distributed in either the minor premise or the major premise.[16][18][12]

Propositional fallacies[edit]

An error in logic that concerns compound propositions.[16]

  1. Affirming a disjunct: P or Q. P. Therefore, not Q.[16][18]
  2. Denying a Conjunct: Not both P and Q.Not P. Therefore, Q.[16][18]
  3. Affirming the consequent: If P then Q. Q. Therefore, P.[16][18][12]
  4. Denying the antecedent: If P, then Q. Not P. Therefore, not Q.[16][18][12]
  5. Negating Antecedent and Consequent (also known as improper transposition): If P then Q. Therefore, if not-P then not-Q.[16][18]
  6. Commutation of Conditionals: If P then Q. Therefore, if Q then P.[16][18]

Fallacies of quantificational logic (also known as fallacies of predicate logic)[edit]

A logical mistake that involves numerical concepts such as some and all.[16]

  1. Existential assumption: All X, if they existed, would be Y. All Y that exist are Z. All X are Z. [16][18][17]
  2. Illicit Conversion (also known as false conversion): All P are Q. Therefore, all Q are P.[16][18][12]
  3. Illicit Contraposition: No S are P. Therefore, no non-P are non-S.[16][18]
  4. Quantifier-Shift Fallacy: Every X has the relation R to some Y. Therefore, some Y has the inverse of relation R to every X.[16][18][12]
  5. Some Are/Some Are Not (also known as unwarranted contrast): Some S are P.Therefore, some S are not P.[16][18]

Probabilistic fallacy[edit]

When the conclusion reached from the premises of an argument violates the laws of probability.[16][note 1]

  1. The Base Rate Fallacy (also known as base rate neglect): Incorrectly ignoring statistical information in favor of irrelevant information to make a judgment.[16][18]
    1. Confusion of the inverse: Given two events A and B, the probability of A happening given that B has happened is assumed to be about the same as the probability of B given A. More formally, P(A|B) is assumed to be approximately equal to P(B|A). It is a fallacy one encounters when using Bayes’ Theorem (as are base rate fallacies in general).[19]
    2. Prosecutor's Fallacy: Jurisprudence in the USA can be described as poorly executed statistical inference done by three unqualified statisticians before a statistically ignorant jury. In Europe, this is not necessarily the case as they appear to understand the importance of Bayesian inference.[note 2] The prosecutor's fallacy occurs when someone overemphasizes the weight of the evidence proving someone's guilt.[21][12]
      1. False Allegations as Proof (blindly trusting the accuser, assuming the guilt of the accused): When people assume that the victim of an alleged crime is telling the truth and this assumption is wrong. This is an ipse dixit fallacy committed by overzealous prosecutors.[note 3]
    3. Defense attorney's Fallacy: When someone downplays the weight of the evidence proving someone's guilt.[21]
      1. Blaming the victim: When a victim's actions are used as proof that some offense against them was justified or didn't occur. This is an ad hominem fallacy commonly used by defense attorneys in cases involving rape.
  2. The Multiple Comparisons Fallacy: A group of statistical studies shows that out of N studies, B number of studies produced result C and D number of studies produced result E. The media reports "Studies show E," ignoring result C.[16][18]
  3. Overfitting: Failing to ignore data outliers resulting in a model that is not representative of the general trend of the data set.[23][12]
  4. Data Dredging (also known as post-designation and data fishing): This is when you test all kinds of different hypotheses against the same set of data until you find something that is statistically significant. This is a fallacy because that statistical result is most likely due to chance.[18][23]
    1. Texas sharpshooter fallacy: A data mining fallacy and pattern recognition error where the arguer makes an ad hoc conclusion from a set of unrelated data without looking for corroborating data.[16][18][12]
  5. The Conjunction Fallacy: A is a subset of B. Therefore, A is more probable than B.[16][18][12]
  6. Disjunction Fallacy: Event A is more probable than the likelihood of event A or event B.[18]
  7. Gambler's fallacy: I lost the last twenty dice rolls -- I'm due for a win, so I better double down![16][18][12]
  8. The Hot Hand Fallacy: I am on a hot streak! Just one more hand! I can't lose![16][18]

Bad reasons fallacy[edit]

Argument A for the conclusion B is bad. Therefore, B is false.[16]

  1. Fallacy fallacy (argumentum ad logicam): Argument A for the conclusion B is fallacious. Therefore, B is false.[16][18]

Fallacy of modal logic[edit]

Formal fallacies in which modalities play a role in creating a fallacious argument.[16]

  1. Modal Scope Fallacy: The most common type of modal fallacy which occurs when placing a proposition in the wrong modal scope.[16][18][12]

Masked man fallacy (Also known as Illicit Substitution of Identicals)[edit]

A fallacy that involves confusion between extensions and intensions.[16][18][12]

Informal[edit]

See the main article on this topic: Informal fallacy

Fallacies of presumption[edit]

Fallacies that occur when one uses a fallacious or unwarranted assumption to establish a conclusion.[12]

Non causa pro causa (also known as false cause)[edit]

Fallacies in which a cause is incorrectly identified.[16][12]

  1. Post hoc, ergo propter hoc: Because event A happened before B, A must have caused B.[16][17][12][24]
  2. Cum hoc, ergo propter hoc (also known as correlation does not imply causation): Concluding that because A is correlated with B, A caused B.[16][18][12]
    1. Confounding causation (also known as joint effect): Asserting X causes Y when, in reality, X and Y are both caused by Z.[17][12][16][25]
    2. Coincidence: Asserting X causes Y when, in reality, the correlation is a statistical anomaly.[16][25]
    3. Reverse causation (or wrong direction): When a cause is mistakenly considered an effect.[17][12][16][25]
  3. Regression fallacy: Something naturally fluctuates. For example, a person gets sick on occasion. When they get sick, they take snake oil as a cure-all. They later feel better because they have reverted to the mean which for them is feeling healthy. They falsely conclude snake oil was a cure even though they only reverted to the mean.[16][18][12]
  4. Magical thinking (or superstitious thinking): Making causal connections between A and B based upon superstition rather than evidence. I danced for rain. It rains a week later. I caused the rain. I wore my lucky baseball cap. My team won. My wearing of the baseball cap has the power to make my team win.[18][12]
  5. Fallacy of the single cause (also known as causal oversimplification, causal reductionism, and the reduction fallacy): When it is assumed that there is a single, simple cause of an outcome when in reality it may have been caused by a number of jointly sufficient causes.[18][12]
    1. Insignificant Cause – One minor factor out several contributing factors is the sole cause.[18][17]

Jumping to conclusions[edit]

Coming to a judgement without taking the time to rationally evaluate the merits of the argument.[18][12]

  1. Accident Fallacy (a dicto simpliciter ad dictum secundum quid): When a rule of thumb is taken to be universally true.[16][18][12]
    1. Ecological Fallacy: Interpreting statistical data about a group to make inferences about an individual of that group and coming to an incorrect conclusion.[18]
      1. Stereotyping Fallacy: Assuming that all individuals of a group have a certain characteristic when this doesn't hold true for all individuals. Example- Stipulating "All men are taller than women," is a stereotype as there are women who are taller than most men and men that are shorter than most women. On the other hand, stipulating "Men are usually taller than women." is not a stereotype fallacy. Rather it is an accurate statistical statement.[18][12]
  2. Hasty Generalization (also know as overgeneralization and converse fallacy of the accident): Taking a few specifics and making a general rule out of them, without the few specifics adequately representing the entire group.[16][18][12]
    1. Unrepresentative Sample (also known as biased sample fallacy and selection bias): Drawing a conclusion about a population based upon a sample that isn't reflective of the population that it is supposed to represent.[18][16][12]
      1. Self –selection - a fallacious way of collecting data where the participants who choose to participate in the study are not likely to be representative of the population that it is supposed to represent (such as online polls).[12]
      2. Double Counting- When something is counted twice resulting in a statistical error. For example, let’s say that one is wishing to determine what statistical percentage of people have a medical condition that could be described as intersex. In order to tabulate this figure, one could include people who have a genetic disorder called MKRH syndrome and people who have a phenotype called vaginal hypoplasia. If one includes both groups unquestioningly, there is likely to be double counting as MKRH syndrome causes vaginal hypoplasia.[18]
      3. Survivorship bias: An unrepresentative sample due to death. Example: Say 80% of people in a population are Christian and 20% are not, and car crashes kill and save lives independent of one's religious beliefs. 80% of the survivors say Christianity saved their life which leaves the false impression that Christianity works because the 80% of Christians who died don't get to tell how Christianity didn't save their life...because they are dead.[18]
      4. Small sample- using a sample size too small to generate statistically relevant conclusions due to insufficient data[12]
        1. Insufficient Statistics: the drawing of statistical conclusions from the small sample size.[12]
        2. Overprecision (also known as Fake Precision): Assuming a prediction is exactly correct for any given point.[18][12]
        3. Anecdotal evidence: Using anecdotal evidence to make a general point. Example: Lorenzen Wright married his high-school sweetheart who is now on trial for his murder. This proves that you should never marry your high-school sweetheart.[16][12]
          1. Pragmatic fallacy: It worked for me -- it'll work for everyone!
    2. Ludic Fallacy: Presuming that your statistic model works in situations where it doesn't.[18]

Selective attention[edit]

Focusing on certain particulars of an argument while ignoring other aspects of it.[18][12]

  1. Availability Heuristic: when certain facts are more easily recalled than others resulting in an unrepresentative sample to draw conclusions from.[12]
    1. Toupee fallacy: I only see evidence for my hypothesis, because evidence against it is inherently hidden from me.
    2. Misleading Vividness: A few dramatic events such as plane crashes give the mistaken imprecision that it is unsafe to fly when, in fact, it is statistically safer to fly than it is to drive.[18][12]
    3. Spotlight fallacy: when highly publicized data on a group is incorrectly assumed to represent a different or larger group.[18]
      1. Tokenism: Rich politician goes to homeless shelter on Thanksgiving and shakes a couple of hands for about an hour then goes home to his or her mansion. News shows the politician shaking hands. Next day the politician gives tax breaks to the 1 percent and raises taxes on the middle class.[18][12]
    4. Historian’s Fallacy (also known as: retrospective determinism): When your boss presumes that you are omniscient and therefore should have known about the ten car pile up that caused you to be late to work.[18]
      1. Dixiecrat fallacy: Dems supported segregation! Dems are racist!
  2. Cherry picking (also known as one-sidedness, suppressed evidence, and the fallacy of exclusion among others): Intentionally only using information that supports one’s position and ignoring the evidence that contradicts it.[16][18][12]
    1. Apex fallacy: Using the best/worst group to generalize to the whole group.[12]
      1. Nutpicking: Using examples that are insane to represent a group.[12]
    2. Lack of proportion - exaggerating or downplaying a piece(s) of evidence that are used to reach a conclusion.[12]
      1. Downplaying – deemphasizing relevant information when coming to a conclusion.[12]
        1. Disregarding Known Science- making claims that ignore and/or contradict scientifically substantiated fact.[12]
      2. Exaggeration – overemphasizing information of questionable relevance when coming to a conclusion.[12]
    3. Argument by Selective Reading: Acting as if the weakest argument made by an opponent was the only one made and focusing one's rebuttal on only that argument.[18]
    4. Oversimplification - making a complicated issue appear simple when it really isn’t.[12]
  3. Confirmation bias: Seeing only evidence that supports ones hypothesis and overlooking evidence that would contradict it.[12]

No True Scotsman[edit]

When groups are redefined on the spot. Example - Person 1: "Christians are inherently moral people." Person 2: "The Catholic priests that molested alter boys were Christian." Person 1: "Well they were not true Christians."[18][12]

  1. Hedging: When you can't defend your claim from someone pointing it out the obvious deficiencies of it so you revise your claim and act as if was the same as the original claim.[18][12]
    1. Overwhelming Exception: Using numerous exceptions to a claim to make it "accurate," but results in the claim having no real meaning. Example- Except for 9-11, the invasion of Iraq, the federal response to Katrina, and the financial crisis, George W. Bush's tenure as President proved that he was skilled at his job.[18]

Category mistake[edit]

Confusing what is true of a part with what is true of the whole.

  1. Fallacy of Composition: Individual things a whole entity is comprised of has characteristics A, B and C etc. therefore the whole entity has characteristics A, B and C.[16][18][12][24]
  2. Fallacy of Division: The whole entity has characteristics A, B and C therefore its parts has characteristics A, B and C.[16][18][12][24]

False dilemma (also known as the Black-or-White fallacy, false dichotomy or false dilemma)[edit]

When two opposing views are presented as the only options when they are not.[16][18][12]

  1. Alternative Advance: When both of the options presented to you are essentially the same thing, just worded differently.[18]

False equivalence[edit]

When you presume that two things are the same when they are not.[26][12]

  1. Moral equivalence: Arguing that two things are morally equal, even though they are not.[26]
  2. Political Correctness Fallacy: When you presume that people's ideas are of equal value or are equally true when they are not. (Think Galileo.)[18]
    1. Argument to Moderation (argumentum ad temperantiam): Presuming that somewhere between two disparate positions there must be a compromise position between them that is correct. Example- Medicare Part D was such a great bill because it was a compromise between the positions of the Republicans and the Democratics. In fact, it was so great that pharmaceutical companies are price-fixing drugs, violating anti-trust laws, and costing American taxpayers billions of dollars. Here is a 60 Minutes expose of just how great the compromise between Republicans and Democrats is for America.[18]
  3. Balance fallacy — Giving equal weighting to both sides of an argument, even if one really doesn't deserve the time.[12]

Inconsistency[edit]

When two assertions are made that contradict one another in such a way that both assertions cannot be true.[18]

  1. Self-refuting idea (also known as contradictio in adjecto and conflicting conditions): A claim that on closer inspection disagrees with itself.[18][12]
    1. Stolen Concept Fallacy: When the thing you are seeking to disprove requires the existence of the thing you are trying to disprove. Example- "Logic can't possibly be a way to derive at truth. To prove to you why I think this way..."[18]
    2. Kettle Logic: A collection of arguments made to try and prove a point but the arguments contradict one another.[18]
  2. Double Standard: Using one set of criterion for one person (or group of people) and another set of criterion for a different person (or group of people) when only one set of criterion should be used.[18][12]
  3. Special pleading: When universal rules no longer apply in this specific instance. Example- I know the law says that there is no left turn on red, but I was in a real hurry...[16][18][12]
    1. Notable Effort: You have made a notable effort while in prison therefore life imprisonment no longer means spending your life in prison.[18]

Fallacies of relevance[edit]

Red herring (Ignoratio elenchi): A group of fallacies which bring up facts or issues which are irrelevant to the argument often in an attempt to distract the opponent and/or audience.[16][18][12][24]

Argument from ignorance (argumentum ad ignorantiam)[edit]

When it is claimed that a proposition is true because it has not yet been proven false or that it is false because it has not yet been proven true.[16][18][12]

  1. Science doesn't know everything: Premise 1: If science (or a person) can't explain X, then Y is true. Premise 2: Science can't explain X. Conclusion: Y is true.
    1. Moving the goalposts: Science explains/discovers the X of the first premise leading to the refutation of the support for Y. New requirement: Well if science can't explain Z then Y is true. Science explains Z. New requirement: Well is science can't explain W...[18]
      1. Inflation of Conflict: If there is not complete agreement on X, Z, and W, then people don't know anything at all.[18]
    2. Confusing Currently Unexplained with Unexplainable: Science hasn't explained how the big bang began (X), therefore Y = it will forever remain unknown.[18]
    3. One single proof — Dismissing all circumstantial evidence in favor of a single "smoking gun" that may not (and may not need to) exist.
  2. Shifting of the Burden of Proof (onus probandi): When one asserts something to be true without evidence for one's position and then asks people to prove them wrong. (A person asserting a fact is the one who has to have proof, not the other way around.)[18][12]
    1. Negative proof (also known as proving non-existence): Arguing that something must exist because there is no evidence it does not exist.[18]
  3. Missing Data Fallacy: One's hypothesis has been proven wrong. One asserts "Well there is yet to be discovered information that will prove one's flawed hypothesis or conclusion to be true."[18]
  4. Appeal to Complexity: I can't stand understand something therefore no one else can either.[18]
    1. Argument from incredulity: P1: One can't imagine how X could be true. P2: (unstated) If X is true, then one could imagine how X could be true. C1: X is false.[18]
      1. Willful ignorance: *fingers in ears* nah-nah-nah-nah-nah, can't heeeeaaaarrrr youuuu![18]

Genetic fallacy[edit]

A genetic fallacy occurs when the origin of a claim is used to establish truth or falsehood rather than the claim's current factual merits.[16][18][12]

Appeal to False Authority (argumentum ad verecundiam)[edit]

Incorrectly asserting that respect given to some authority proves the assertion to be true.[16][18][24]

  1. Ultracrepidarianism: When a source is quoted outside their expertise, as if expertise in one field extended to another.
    1. Professor of nothing: When a source is introduced as "Prof." or "Dr.", yet they aren't.
    2. Appeal to celebrity: When a source is supposedly authoritative because of the respect people give them.[18]
  2. Ipse dixit: When a source is the person making the argument. Example - Claimant: Donald Trump stole 10 million dollars from me. Judge: What proof do you have of this? Claimant: I said so. Judge and Jury: That works. Awards claimant 10 million dollars.
  3. False Attribution: Using an unreliable, fabricated, irrelevant or other form of untrustworthy source as the basis of ones argument.[18]
    1. Appeal to Definition (argumentum ad dictionarium): If the dictionary says what I think something means,the dictionary is right. If not, find a new dictionary.[18]
    2. Generalization from fictional evidence: Using a fake story to make a general point.
    3. Linking to authority: When a source is "cited" in-text yet the reference doesn't exist / is irrelevant / says something else.
    4. Anonymous authority: When a source is quoted (or supposedly quoted), but no name is given.[18]
      1. Argument from Hearsay: When the source doesn't have first-hand knowledge of the event but knows somebody who knows somebody who said that this is what happened. (It is not hearsay if the source states something so do that instead.)[18]
    5. Quote mining (it is also a fallacy of accent): When an authority is selectively quoted to distort their views, or misquoting someone to gain the appearance of authority.[16][18][12]
    6. Invincible authority: When a source is the entirety of an argument.
      1. Amazing Familiarity: When you know God is omniscient because you are omniscient.[18]
  4. Alleged Certainty: Asserting that a conclusion is certain because everyone knows it to be true even though there are people who would rationally disagree with one's assertion.[18]
    1. Appeal to common sense: Arguing that the conclusion one reached is supported by “common sense." As many of the readers of this page probably realize, there is no agreed upon common sense. Or, if it does exist, it is awfully fallacious.[18]
    2. Appeal to Self-evident Truth: Arguing that something is true because it is "self-evident." What is or is not self-evident is highly debatable and subjective by definition.[18]
      1. Fantasy Projection: Expecting other people to accept your subjective interpretation of experiences as the basis for objective truth.[18]
    3. Proof Surrogate: To prove X, I will assert it to be true without providing any evidence for my conclusion, but I will assert it confidently so you will believe me.[18][12]
  5. Blind Authority Fallacy (also known as the Nuremberg defense and divine authority): When one believes something to be true simply because the person saying it is in charge[18]
    1. Appeal to the Law: Using whether something is illegal or not as the basis for morality.[18]
      1. Rights To Ought Fallacy: Confusing what one has a legal right to do with what one ought to do. For example, one has the legal right to protest a march for breast cancer awareness. Having that right doesn’t mean that one ought to do it though.[18]
    2. Appeal to Heaven (deus vult): Arguing that X is true because only by obeying it can you go to heaven. This is also a fallacy of vacuity.[18]
  6. Appeal to Consequences of a Belief (argumentum ad consequentiam): Whether something is true or not depends on whether the consequences of it being true are desirable or undesirable.[16][18][12]
    1. Appeal to Force (argumentum ad baculum): Using force or the threat of it to provide support to ones argument. The negative outcomes are being actualized by the one making the argument.[18][16][12][24]
      1. Argument by censorship: I have created silence; this shows that my point cannot be responded to!
      2. Galileo gambit — If someone is going against the tide of popular thinking, they must be right because the likes of Galileo were right, while in reality, Galileo was right because he had evidence[18]
        1. Argumentum ad martyrdom: Using the fact that someone died for a cause or belief to prove that the cause or belief he died for was true.
    2. Righteousness Fallacy: Assuming that if a person has good intentions, then they also know the truth.[18]
    3. Self-Righteousness Fallacy: Assuming that your good intentions proves that you understand truth.[18]
    4. Wishful Thinking: The desire for something to be true makes it true.[16][18][12]
      1. Appeal to Possibility: The fact that something isn't impossible, however improbable, means that it is true.[18]
  7. Argumentum ad populum (also known as the bandwagon fallacy, appeal to common belief, and the authority of the many among others): Most people believe X to be true therefore it must be true.[16][18][12][24]
    1. Groupthink: When one reasons the same way everyone else does in their group out of a desire for social acceptance or because one is too stupid to think independently.[12]
    2. Appeal to tradition (argumentum ad antiquitatem): Because it's always been that way, it's absolutely the right way![18][12]
    3. Appeal to Popularity (argumentum ad numeram): The popular thing to do or believe in is also the right thing to do or believe in.[18][12]
      1. Silent Majority: When a source is supposedly authoritative because of the popularity of their views, yet there is no evidence of the popularity of their views
Ad hoc (also known as making stuff up)[edit]

When some idea is asserted purely to shore up some other idea.[18][12]

  1. Just Because Fallacy (not to be confused with ipse dixit, a.k.a. because I said so): Student: Why is the sun yellow? Teacher: Just because. Now focus on the rote memorization that will make you pass the standardized tests and make me look good.[18]
  2. Smokescreen - offering up irrelevant information to obscure the relevant information.[12]
    1. Quantum Physics Fallacy: Hmmm... how do I prove point X? Oh I know. People don't understand quantum physics so I will say that point X is proven by the uncertainty principle.[18]
    2. Zero-Sum Fallacy: Hmmm... now how do I now prove point Y? I think I will use game theory and call it a zero sum game. This is a fallacy commonly found in economics. There are valid ways to use game theory in economics but you have got to be smart about it like this guy.Wikipedia's W.svg[26]
    3. Spiritual Fallacy: When something can not be explained using conventional logic, the person claims that its correct in a 'spiritual' way. Example- Person 1: The Holy Spirit, God, and Jesus are all one entity but they are also three separate entities at the same time. Person 2: Do you mean that the Holy Spirit, God, and Jesus are three parts of a greater whole? Person 2: No. Each of them are the whole thing. Person 1: If the Holy Spirit, God, and Jesus are all the whole thing, then why are they considered to be three separate entities? Person 2. Stop asking questions. It is correct in a spiritual way.[18]
    4. Deepity: "Love is more than just chemicals. It is also the quantum fluctuations of the sublime." "Oh Sergio! You are so deep! Take me now!" This is also a subset of failure to elucidate.
    5. Chewbacca Defense: "Cochran: Ladies and gentlemen of this supposed jury, I have one final thing I want you to consider. Ladies and gentlemen, this is Chewbacca. Chewbacca is a Wookiee from the planet Kashyyyk. But Chewbacca lives on the planet Endor. Now think about it; that does not make sense! Gerald Broflovski: Damn it! ... He's using the Chewbacca defense!"
  3. Lying – Intentionally saying something that isn’t true.[12]
    1. Argumentum ex culo: When some fact is cited to defend something, but the fact is entirely fictional.
    2. Rationalization (also known as making excuses): Inventing a reason for something instead of giving the real reason. Example- “I can’t go on a date with you because I am too busy with school right now to get involved with someone.”[18][12]
  4. Misrepresentation- a mischaracterization of an opposing position.[12]
    1. Straw man — Distorting an opponent's position for greater rhetorical flexibility like what Ayn Rand did with socialism.[16][18][12]
  5. Irrelevant reason - When one uses premises that are not relevant to the issue at hand.[12]
    1. Psychogenetic Fallacy: Assuming that there is a psychological reason why an argument is invalid. Example- You think I am dumb because you are on your period.[18]
    2. Confusing an explanation with an excuse - Assuming that someone’s explanation for bad behavior somehow excuses it.[18][12]
  6. Slothful induction (also known as appeal to coincidence): Ignoring the strongest conclusion of an inductive argument to focus on a weaker one.[18]
    1. Least Plausible Hypothesis: Favoring a hypothesis with a lower probability of likelihood over one that is far more probable.[18]
    2. Far-Fetched Hypothesis: Favoring a hypothesis that is not plausible over the more probable hypothesis.[18][12]
Ad hominem[edit]

When the source of the argument is attacked, rather than their idea.[16][18][12][24]

  1. Association fallacy: When someone's associations are used as evidence against their ideas.[16][18][12]
    1. Bad Seed: Arguing that the “Apple doesn’t fall far from the tree.”[12]
    2. The Hitler Card (also known as Reductio ad Hitlerum): Hitler spoke German and you are learning to speak German as a second language, therefore your arguments have no merit as you are just like Hitler.[16][18]
  2. Identity Fallacy: When the truth of an argument is determined by one's physical appearance, social class, or other form of social identity.[18]
    1. Bulverism: Person 1 (a Chinese immigrant): Not all Chinese people are good at math. Person 2: Yes they are. And why should I believe you? You are Chinese![18]
  3. Fallacy of opposition: When someone's opposition to your opinion is taken as proof of their incorrectness.[18]
    1. Gadarene Swine Fallacy: Person X is not adhering to our groupthink. Person X is wrong.[18][12]
      1. Traitorous Critic (Fallacy ergodecedo): Dismissing a person’s criticism of how their group does something on the basis that if they don’t like how something is done, then they can leave. Example: Person 1: England doesn’t have as many problems with gun violence because of their tougher gun laws. Person 2: Well if you like it so much, why don’t you just move there?[18]
  4. Appeal to bias (also known as ad hominem circumstantial and vested interest) - Arguing that someone’s argument has no merit because he or she stands to profit from it being true in some way.[18][12]
    1. Shill gambit (also known as faulty motives): Asserting an arguer is working for someone and spreading disinformation.[12]
  5. Ad Fidentia (argumentum ad fidentia): attacking a person's self-confidence.[18]
    1. Argumentum ad cellarium: Accusing the arguer of still being in "mom's basement".
  6. Poisoning the well: Where an opponent is pre-painted as terrible.[18][12]
    1. Demonization: When one's opponent is depicted as unequivocally terrible.
  7. Tu quoque (argumentum ad hominem tu quoque): Where a criticism is falsely dismissed because its author is also guilty of the charge.[16][18][12][24]
    1. Whataboutism: Tu quoque, USSR style!
  8. Subjectivist Fallacy (also known as: relativist fallacy):When some objective fact is asserted to be true for some people but not true for others..[18][12]
  9. Damning with faint praise: When someone is attacked through praise of an achievement that isn't praiseworthy or isn't significantly praiseworthy, suggesting that no achievements worthy of praise exist.
  10. Two wrongs make a right: A Hatfield: A McCoy killed our kin! That ain't right! Lets get em! (kills a McCoy). A McCoy: A Hatfield killed our kin! That ain't right! Let's get em! (Kills a Hatfield) (Repeat)[16][18][12]
  11. Tone argument: If you can't keep it civil, you clearly can't make truthful statements!
Etymological fallacy[edit]

Confusing the original meaning of a word and its current meaning.[16][18][12]

Emotional appeal[edit]

Evaluating an argument based on feelings rather than logic.[16][18][12]

  1. Appeal to novelty (argumentum ad novitatem): Arguing that a claim is valid because it is novel.[18][12]
  2. What's the harm: It's just some water (and your payment of $50); what harm can it do?
  3. Appeal to nature (argumentum ad naturam)— Arguing that something is good because it is "natural".[18]
  4. Argument from Age: It's right because the Maya/Chinese/Hebrews said it thousands of years ago![18]
  5. Argument to the Purse argumentum ad crumenam: Using ones possession of money (or lack of it) to prove the truth of a claim.[18]
    1. appeal to wealth: I have made a bunch of money so anything I tweet must be true![18][12]
    2. Appeal to poverty: My lack of money proves that I know the secret to happiness.[18]
  6. Appeal to Accomplishment (also known as appeal to success): I have three doctorates at BS University and have written 7 best-selling books on the subject of the quantum dream states therefore anything I say is true.[18]
  7. Appeal to confidence/Trust: Trust me, I know what I'm doing.[18]
  8. Appeal to Intuition: I have a gut feeling that something is true, therefore it is.[18]
    1. Appeal to Stupidity: How you feel about something is more important than its factual basis.[18]
  9. Appeal to gravity: I'm the only one up here who takes this seriously. Disregard these jokers -- I have the truth.
  10. Appeal to Desperation: Something must be done about these illegal immigrants. Let's build a border wall![18]
  11. Appeal to Normality: It is normal in America to be in debt therefore it is nothing to worry about. Let me tell you about our financing options...[18]
  12. Appeal to Common Folk: Joe the Plumber is a common man. He says to do X. You are a common man, therefore X is the right thing to do.[18]
  13. Appeal to closure: Crime X occurred. Person Y looked suspicious but no evidence connected him to it and no other suspects were found. City arrests person Y ought of a desire to close the case.[18]
    1. Scapegoat: Using someone to take the blame, like what Facebook is doing with Aleksandr Kogan and what Democrats do with Republicans (and vice versa).[18]
  14. Appeal to flattery: What a lovely fallacy you have there! You must be a smart person, someone who'd find quantum healing quite fascinating.[18]
  15. Appeal to (insert your favorite emotion).[18]
    1. Appeal to shame: Would you say that in front of your mother?
    2. Appeal to Pity (argumentum ad misericordiam): Using the emotion of pity to distract from the truth of an argument. Many people in the USA view innocent by reason of insanity as an example of this fallacy which has lead to the adoption of guilty but mentally ill laws.[16][18][24]
    3. Argumentum ad fastidium: Ugh, that's so gross -- it must be false.
    4. Appeal to Anger (argumentum ad iram): When Rush Limbaugh's anger is used to prove the claims he is making.[18]
    5. Appeal to Hatred/Spite (argumentum ad odium): Don't you hate it when people point out your logical fallacies? I know I do. So come join me in my campaign against logic!"[16][18]
    6. Appeal to Pride (Argumentum ad Superbiam): You know what is wrong with this country? People are no longer proud to be an American. Well I am and together we can make American great again![16]
    7. Appeal to fear (argumentum ad metum, argumentum in terrorem): We're surrounded by logical fallacies! RUN!![16][18]
  16. Appeal to Ridicule (reductio ad ridiculum): Some people think I am ridiculous. But you know who is really ridiculous? It is all of these liberals who voted for someone who wasn't even born in America! That birth certificate Obama showed was clearly a fake.[18]
  17. Loaded language (also known as prejudicial language): Using terms such as “hard-working Americans” that elicit strong emotions in the listener in order to establish the truth of an argument.[18][12]

Fallacies of vacuity[edit]

Fallacies that "(do) not establish what the proponent of the argument intended because it doesn't put forward a substantive claim in favor of the conclusion."[27]

  1. Circular reasoning (also known as circulus in demonstrando): A is true because of B. B is true because of A.[18][12]
    1. Begging the Question (also known as petitio principia): Assuming the initial point. Claim A assumes A is true. Therefore, claim A is true.[16][18][27][12][24]
      1. Subverted Support: Trying to explain how some phenomenon occurred when there is no evidence that the phenomenon occurred. Example – Conservative Christian explanations of the great flood and Noah’s ark.[18]
      2. Appeal to faith: Arguing that one must use faith rather than reason to understand something to be true.[18]
      3. Complex Question Fallacy (also known as plurium interrogationum or loaded question): Asking a question, which has an assumption built into it, so that it can't be answered without appearing to agree to the assumption, or else appearing evasive by questioning the assumption. To be distinguished from a Leading question, which is not a fallacy, but is a way of suggesting the desired answer by how the question is phrased. "Are you still beating your wife?" is a loaded or complex question, for it assumes that at one time you did beat your wife; while "You weren't beating your wife, were you?" is a leading question, for it suggests the simple answer no.[18][12][24]
  2. Self-Sealing arguments: arguments that can't be argued against because they are constructed in a way that seals itself off from criticism.[27][18]
    1. Not even wrong (also known as unfalsifiability): an argument or explanation that purports to be scientific but is based on invalid reasoning or speculative premises that can neither be proven correct nor falsified.[18][12]
      1. Hypothesis Contrary to Fact: If Alexander the Great hadn’t died, then the Greek empire wouldn’t have fought amongst itself and the world would be far more intelligent than it is now as it would have been run by the Greeks.[18]
    2. Conspiracy theory: Of course I can’t prove JFK was assassinated by Ted Cruz’s dad. The government has covered it up! [18]
    3. Homunculus Fallacy: If I say X, and then say that X proves that X is true, then I win![18]
  3. Meaningless Question: How much wood could a woodchuck chuck if a woodchuck could chuck wood?[18]

Weak analogy[edit]

Using an analogy that is too irrelevant for it to be used to prove or disprove an argument.[16][18][12][24]

  1. Faulty Comparison: Comparing two things as if they were related when they are not in order to convey the idea that one is better than the other is. Example - X motorcycle gets 5 times better gas mileage than the best selling Y automobile.[18][12]
  2. Incomplete Comparison: A comparison that fails to state what it is being compared to. Example - Our garbage bags are 40% stronger![18]
  3. Extended analogy: Example. P1 – Dimitrios Pagourtzis used a shotgun to kill. P2 – Hunters use a shotgun to kill. C1 – Therefore, hunters are like Dimitrios Pagourtzis.[18]
    1. Reductio ad Hitlerum — Saying something is bad because Hitler (allegedly) did it. Sometimes called "Hitler Ate Sugar."[16][18]
  4. Appeal to the Moon (argumentum ad lunam): Arguing if we can put a man on the moon, then surely we can cure trisomy 13.[18]
  5. Appeal to Extremes: Misrepresenting a reasonable argument by using extreme examples to try and prove the argument to be fallacious.[18]

Fallacies of clarity[edit]

Fallacies that lead to logical confusion because of a lack of logical or linguistic precision.[12]

Vagueness[edit]

Fallacies pertaining to a lack of distinctness.[16]

  1. Argument of the Beard (also known as the fallacy of the heap and the continuum fallacy): When one argues that there is no difference between two extremes of a spectrum because one is not sure when a man goes from being clean shaven to having a beard.[16][18][12]
    1. Science was wrong before: And therefore it can never be right.
    2. Wronger than wrong: The fallacy of assuming that different degrees of "wrong" are the same.
    3. Not as bad as (also known as relative privation): A moral fallacy that says because B is worse than A, A should be seen as something good. Example - Sure you may have lost your arm, but at least it wasn't both of your legs.[18]
    4. Nirvana fallacy: Claiming that a realistic solution is useless because it is not as good as an idealized perfect solution.[18][12]
  2. Slippery slope: A leads to B which leads to C which leads to D which leads E which leads to zebras having relations with elephants.[16][18][12][24]

Fallacy of ambiguity[edit]

Making something unclear to allow its misuse.[16][18][12][24]

  1. Equivocation: Substituting the meaning of a given word in one context for another context that is inappropriate in order to make your argument.[16][18][12][24]
    1. Intensional (also known as ambiguous middle term): using words or phrases that are open to more than one interpretation and treating the different meanings for the same word or object as being equivalent when the differences matter.[12][16]
      1. Appeal to Equality: Using the ambiguous and emotionally charged word of ‘equality’ to argue that people should be treated equally when what exactly that means is far from apparent.[18]
      2. Use-Mention Error: Confusing a descriptive word of a thing with the thing itself. Example: Anslem’s ontological argument.[18]
  2. Fallacy of amphiboly: When a sentence, because of its grammar, structure, or punctuation, can be interpreted in multiple ways.[16][12][24]
    1. Scope fallacy: When the scope of a logical operator (eg, "not", "some", or "all") is vague and allows for misinterpretation and incorrect conclusions.[16][12]
      1. Fallacy of Every and All: Using words like every, all and some in way X in statement 1 and using these words in way Y in statement 2 and assuming that the meaning of the word hasn’t changed.[18][12]
    2. Type-Token Fallacy: A fallacy that confuses types of things with tokens (or number of things) Example- Person 1: We sell dozens of signs(type), anything from stop signs to deer crossing signs. Person 2: How do you stay in business if you only sell dozens of signs?(token)[18]
  3. Fallacy of accent: When the meaning of a text is changed by what word or words are stressed, and stress is unclear. For example, "She is a born-again virgin?" is a different form of disbelief than "She is a born-again virgin?" A fallacy occurs when something is stressed in way X in statement 1 and way Y in statement 2. [16][18][12]
    1. Quoting Out of Context (also known as Contextomy): When an authority is selectively quoted to distort their views.[16][18][12]
  4. Reification (also known as hypostatisation): When an abstraction is treated as if it was something concrete.[18][12]
    1. Anthropomorphism: the attribution of human traits to animals, inanimate objects, or a deity(s).[18][12]
      1. Pathetic fallacy: Attributing human traits to inanimate objects.[12]

Fallacy of definition[edit]

Fallacies that convey confusion about the exact meaning of a word or phrase.

  1. Suppressed correlative: Attempting to redefine two mutually exclusive options so that one encompasses the other. Example - Person 1 :That haunted house was pretty good. Were you scared or not? Person 2: Well, if you define scared as not having complete understanding of the future, then I am always scared.[18]
  2. Circular definition: A circular definition.[18]
  3. Phantom distinction (also known as distinction without a difference): When someone spends time arguing for the superiority of one term over another (rather than the intended debate), yet there is no effective difference.[18]
  4. Definist Fallacy: When one makes up definitions with no real meaning and/or with loaded language in order to make one's position easier to defend.[18][12]
  5. Failure to Elucidate (obscurum per obscurius): Purposefully making a definition more difficult than it needs to be. It is similar to deepity.[18][12]
    1. Proof by Intimidation (argumentum verbosium): Purposefully making one's argument incomprehensible in order to intimidate those who would object to the premises if they could understand what was being said.[18]

Conditional[edit]

See the main article on this topic: Conditional fallacy

For the purpose this list, a conditional “fallacy” is an argument that may or may not be fallacious depending on how the argument is constructed. The fallacious forms of the argument can be placed in the informal category section (and many such fallacies are already listed there).

  1. Appeal to authority: When an appeal to authority is done correctly, then it can be called an appeal to a qualified authority and is not a fallacy. When it is done incorrectly, it can be called an appeal to false authority. Many of the appeals to false authority are listed in the informal fallacy section. Determining what is or is not a qualified authority is the subject of epistemology and it is beyond the scope of this fallacy list. While determining an authority's qualifications is often viewed from a scientific vantage point, it is not limited to that field of study. The “He said she said” problem is also a question of whether an authority is qualified or not.[12]
  2. The Is/ought problem (also known as Hume’s law): The is/ought problem stipulates that “What is” is fundamentally distinct from “What ought.” Consider the issue of black rhinos. Descriptions about what is happening to black rhinos (what is) cannot determine whether rhinos ought to be environmentally protected or allowed to go extinct (what ought). The ought is a human value that is associated with the “what is” but it is not a “what is” itself as it is contingent on subjective experience which varies from person to person (though there are oughts that are more universal than other ones). Most of the problems pertaining to the is/ought problem have been placed in the conditional category as they are contingent on the values a person or society stipulates to be true, though some of the fallacies associated with is/ought problem have been placed in the informal category due to relatedness to other fallacies. For example, the rights to ought fallacy was placed under the appeal to the law fallacy due to there close association. The following are fallacies associated with the is/ought problem that are often seen as being examples of fallacious reasoning.[12]
    1. Moralistic Fallacy: Concluding “what ought” determines “what is.” Example- Homosexuality ought not to occur and therefore it is not something that is natural.[18]
    2. Naturalistic fallacy: Concluding “what is” determines “what ought.” Example- Pedophilia is natural and therefore it ought to be allowed.[18][12]
    3. McNamara Fallacy: Making a decision based only upon things that can be quantified and ignoring things that have a qualitative component. Example- Quantitative argument made: Denying education to people that are here illegally will save taxpayers X amount of dollars. Qualitative argument ignored: Seven-year-old is on the street instead of school because his parents are at work and he or she has no adult supervision.[18]
    4. Economic fallacies: Economics can be thought of as collective ought. We ought to promote laissez faire capitalism or we ought to promote socialism, for example. Given that economics is entangled with what people believe ought to occur, economic fallacies can be characterized as a subcategory of the is/ought problem.
      1. Hyperbolic discounting - When one chooses to ignore the future in order to focus on present rewards. Example: Present: Fracking boosts the local economy! Future: Florida is under the sea.[12]
      2. Sunk cost: I have X amount of money searching for this sunken treasure and its not anywhere where I thought it would be. Well I better spend some more money or else all the money I spent would have been wasted.[18]
      3. Broken window fallacy: A fallacy that asserts that the destruction of property in things like natural disasters actually boosts the economy. It fails to factor in what the money would otherwise be used for if it wasn't being used for reconstruction.[18]
      4. Just In Case Fallacy: Basing ones judgement on the worst-case scenario without adequately factoring in the cost-to-benefit ratio that would cause one to come to a different conclusion. For example, one could conclude that one should spend money on flood insurance for a home in the middle of the Mojave desert due to the very unlikely scenario that changing weather patterns could cause ones home to be caught in an unprecedented deluge of water.[18]
      5. Game theory: Game theory fallacies are conditional. When game theory is done properly as it was by John NashWikipedia's W.svg, then it is not a fallacy. When it is done improperly, then it is ad hoc.[26]

Argumentative[edit]

For the purposes of this list, argumentative fallacies are ones that occur in communication, both the verbal and written forms of it. These fallacies often incorporate many of the informal fallacies listed above when they are presenting information.

  1. Having Your Cake: Person 1- Argument X. Person 2- Argument Y (which contradicts argument X) Person 3- Both X and Y are good arguments.[18]
    1. If-by-whiskey: Using words with strong connotations to hide the fact that one is supporting both sides of an issue and therefore not stating a position.[18]
  2. Slanting: presenting a false representation for a particular argument by misrepresenting, falsifying, misconstruing, and/or suppressing evidence.[12]
    1. Lying with Statistics: Using flawed statistics or a biased presentation of a statistical outcome to convey the idea that one’s position has more support for it than it does.[18]
    2. Argument by Gibberish: Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children (the title for Andrew Wakefield’s paper in the Lancet.)[18]
      1. Alphabet Soup: Using a lot of acronyms to make the thing you are saying impossible to understand.[18]
    3. Smear tactic: attacking an opponent’s character or position in an untruthful way.[12]
    4. Spin Doctoring: Seeking to deceive people by presenting deceptive information that creates a distorted view of reality tailored to one’s agenda. [18]
    5. Shoehorning: Current event X happens. Someone with an agenda uses X to show how their agenda is correct even though there is no rational connection between the two events. Example: A devastating earthquake hits Haiti. A religious commentator says Haiti is paying for its pact with the devil.[18]
  3. Style over substance fallacy: Using language or rhetoric (ethos or pathos) to enhance the appeal of an argument, but not its validity, or arguing the method of presentation affects the truth of a claim.[18]
    1. Escape hatch: When some rhetorical technique is used to evade the burden of proof.
    2. Handwave: the act of glossing over a difficult component in an argument, by ignoring or distracting from it.
    3. Argument by Fast Talking: When one talks like an auctioneer to convey the idea that one is really intelligent and therefore must be right.[18]
    4. Gish Gallop: The debate tactic of drowning your opponent in a flood of individually-weak arguments in order to prevent rebuttal of the whole argument collection without great effort.
    5. Argument by Personal Charm: Using ones charm or sex appeal to win over an audience rather than reasoned arguments.[18]
    6. Argument by Emotive Language: Using loaded language in an argument instead of rational arguments based on statements of fact in order to persuade the listener to ones position.[18]
    7. Hypnotic Bait and Switch: When you begin with a bunch of uncontroversial statements that the listener will agree with then switch to a controversial statement to get the listener to agree with that statement as well. It is a common sales technique.[18]
      1. Motte and bailey - A combination of bait and switch and equivocation: Pretending a defensible but not very useful argument is the same as a more useful, but much less defensible one.
  4. Avoiding the Issue: Person 1- There are reports of you having an affair with your intern. Person 2: Let me tell you about my new tax plan.[18][12]
    1. Avoiding the Question: When one avoids addressing a specific question rather than an entire issue.[12]
  5. Argument by Pigheadedness: Stubbornly refusing to accept rational counter arguments to one’s position without providing any reasons as to why the counter arguments are wrong.[18]
  6. Quibbling – focusing on a minor point and falsely believing that this minor point undermines the larger issue.[12]
    1. Logic Chopping: This is when you are being nitpicky about an issue. Sometimes being incredibly precise about what one is saying is needed such as in scientific papers, but in everyday life it is often times useful to talk in more general terms than to get caught up in the details.[18][12]
  7. Argumentum ad nauseam (argument by repetition): If you say something often enough to make people vomit, you win.[18]
    1. Argument from silence (argumentum e silentio): The lack of response to my point makes my point correct![18]
    2. Argument by assertion: If you say something enough times, it eventually becomes true and therefore you win the argument.


Fallacy collections[edit]

There are lots of fallacy collections on the Web. Some of them promote a particular agenda, but most fallacies listed in them are real and present in arguments everyday. Unfortunately, many are deprecated.

Here is a list of websites, ordered roughly by usefulness:

  1. Fallacy Files(link)
    1. Taxonomy of Logical Fallacies(link)
    2. Glossary(link)
    3. What is a logical fallacy?(link)
  2. Your Logical Fallacy Is(link)
  3. International Encyclopedia of Philosophy(link)
  4. Secular Web(link)
  5. Nizkor Project(link)
  6. Skeptic's Dictionary(link)
  7. About.com: Agnosticism/Atheism(link)
  8. Arthur Schopenhauer(link)
  9. Stephen's Guide to the Logical Fallacies(link)
  10. Dr. Michael LaBossiere(link)
  11. Free Dictionary(link)
  12. Bruce Thompson(link)
  13. Don Lindsay(link)
  14. Art of Debate(link)
  15. George Boeree(link)
  16. Philosophy in Action(link)
  17. Daniel Kies(link)
  18. L. Van Warren(link)
  19. Agent Orange(link)
  20. Humanist Discussion Group(link)

Deprecated ones, listed ad hoc:

  1. Sinclair Community College(link)
  2. Global Tester(link)
  3. Anti-Mormon Illogic(link)
  4. Objectivism(link)
  5. Evolution_V_Creation forums(link)
  6. Peter A. Angeles(link)
  7. Sine Wave(link)
  8. Carleton University(link)
  9. P5(link)
  10. Mathenomicon(link)
  11. Vanessa Hall(link)
  12. J. P. Craig(link)
  13. Informal Fallacies(link)
  14. Autonomist(link)
  15. Gordon, Hanks, & Zhu(link)
  16. Freemasonry(link)
  17. Taking Sides(link)
  18. Jeff Richardson(link)
  19. Chisnell.com(link)

See also[edit]

RussianWiki.png
Русскоязычным вариантом данной статьи является статья Логическая ошибка.
Icon fun.svg For those of you in the mood, RationalWiki has a fun article about Justification generator.

External links[edit]

Notes[edit]

  1. This was placed in the formal category due to the fact that statistics are based in mathematical logical proofs.
  2. Using some form of statistical inference is the only mathematically valid way to evaluate evidence and determine the likelihood of guilt and innocence, but using Bayesian statistics is against USA's laws.[20]
  3. According to a federally funded study made available online by the National Criminal Justice Reference Service, 2-8% of reported rapes in Los Angeles, California were false allegations.[22]

References[edit]

  1. http://philosophynow.org/issues/51/A_Logical_Vacation
  2. http://www.fallacyfiles.org/introtof.html
  3. http://www.fallacyfiles.org/probfall.html
  4. http://www.theskepticsguide.org/resources/logical-fallacies
  5. http://www.logicalfallacies.info/
  6. http://www.nizkor.org/features/fallacies/
  7. http://www.theskepticsguide.org/resources/logical-fallacies
  8. http://www.logicalfallacies.info/
  9. http://www.reddit.com/r/AdviceAnimals/comments/4n6auf/wealthy_americans_can_win_any_fight/d41iwz7
  10. http://medium.com/debating-london/logical-fallacies-and-how-to-beat-them-f8c281c25954#.w0oyudsy6
  11. http://plato.stanford.edu/entries/omnipotence/
  12. 12.000 12.001 12.002 12.003 12.004 12.005 12.006 12.007 12.008 12.009 12.010 12.011 12.012 12.013 12.014 12.015 12.016 12.017 12.018 12.019 12.020 12.021 12.022 12.023 12.024 12.025 12.026 12.027 12.028 12.029 12.030 12.031 12.032 12.033 12.034 12.035 12.036 12.037 12.038 12.039 12.040 12.041 12.042 12.043 12.044 12.045 12.046 12.047 12.048 12.049 12.050 12.051 12.052 12.053 12.054 12.055 12.056 12.057 12.058 12.059 12.060 12.061 12.062 12.063 12.064 12.065 12.066 12.067 12.068 12.069 12.070 12.071 12.072 12.073 12.074 12.075 12.076 12.077 12.078 12.079 12.080 12.081 12.082 12.083 12.084 12.085 12.086 12.087 12.088 12.089 12.090 12.091 12.092 12.093 12.094 12.095 12.096 12.097 12.098 12.099 12.100 12.101 12.102 12.103 12.104 12.105 12.106 12.107 12.108 12.109 12.110 12.111 12.112 12.113 12.114 12.115 12.116 12.117 12.118 12.119 12.120 12.121 12.122 12.123 12.124 12.125 12.126 12.127 Internet Encyclopedia of Philosophy by Bradley Dowden
  13. Cross-Gender Supervision in Prison and the Constitutional Right of Prisoners to Remain Free from Rape by Flyn L. Flesher William & Mary Journal of Women and the Law Volume 13 Issue 3 Article 8
  14. An Ethical Dilemma In Corrections Albert De Amicis August 21, 2005
  15. Barring Male Guards for Female Inmates Might Violate Title VII, Ninth Circuit Rules By Kevin P. McGowan July 8, 2014 Labor & Employment on Bloomberg Law
  16. 16.00 16.01 16.02 16.03 16.04 16.05 16.06 16.07 16.08 16.09 16.10 16.11 16.12 16.13 16.14 16.15 16.16 16.17 16.18 16.19 16.20 16.21 16.22 16.23 16.24 16.25 16.26 16.27 16.28 16.29 16.30 16.31 16.32 16.33 16.34 16.35 16.36 16.37 16.38 16.39 16.40 16.41 16.42 16.43 16.44 16.45 16.46 16.47 16.48 16.49 16.50 16.51 16.52 16.53 16.54 16.55 16.56 16.57 16.58 16.59 16.60 16.61 16.62 16.63 16.64 16.65 16.66 16.67 16.68 16.69 16.70 16.71 16.72 16.73 16.74 16.75 16.76 16.77 16.78 16.79 16.80 16.81 16.82 16.83 16.84 Fallacy Files by Gary N. Curtis, accessed 2018
  17. 17.0 17.1 17.2 17.3 17.4 17.5 17.6 http://web.stanford.edu/~jonahw/PWR1/LogicalFallacies.htm
  18. 18.000 18.001 18.002 18.003 18.004 18.005 18.006 18.007 18.008 18.009 18.010 18.011 18.012 18.013 18.014 18.015 18.016 18.017 18.018 18.019 18.020 18.021 18.022 18.023 18.024 18.025 18.026 18.027 18.028 18.029 18.030 18.031 18.032 18.033 18.034 18.035 18.036 18.037 18.038 18.039 18.040 18.041 18.042 18.043 18.044 18.045 18.046 18.047 18.048 18.049 18.050 18.051 18.052 18.053 18.054 18.055 18.056 18.057 18.058 18.059 18.060 18.061 18.062 18.063 18.064 18.065 18.066 18.067 18.068 18.069 18.070 18.071 18.072 18.073 18.074 18.075 18.076 18.077 18.078 18.079 18.080 18.081 18.082 18.083 18.084 18.085 18.086 18.087 18.088 18.089 18.090 18.091 18.092 18.093 18.094 18.095 18.096 18.097 18.098 18.099 18.100 18.101 18.102 18.103 18.104 18.105 18.106 18.107 18.108 18.109 18.110 18.111 18.112 18.113 18.114 18.115 18.116 18.117 18.118 18.119 18.120 18.121 18.122 18.123 18.124 18.125 18.126 18.127 18.128 18.129 18.130 18.131 18.132 18.133 18.134 18.135 18.136 18.137 18.138 18.139 18.140 18.141 18.142 18.143 18.144 18.145 18.146 18.147 18.148 18.149 18.150 18.151 18.152 18.153 18.154 18.155 18.156 18.157 18.158 18.159 18.160 18.161 18.162 18.163 18.164 18.165 18.166 18.167 18.168 18.169 18.170 18.171 18.172 18.173 18.174 18.175 18.176 18.177 18.178 18.179 18.180 18.181 18.182 18.183 18.184 18.185 18.186 18.187 18.188 18.189 18.190 18.191 18.192 18.193 18.194 18.195 18.196 18.197 18.198 18.199 18.200 18.201 18.202 18.203 18.204 18.205 18.206 18.207 18.208 18.209 18.210 18.211 18.212 18.213 18.214 18.215 18.216 Dr. Robert Bennett, Logically Fallacious, accessed 2018
  19. http://link.springer.com/content/pdf/10.3758/BF03195278.pdf
  20. Neglect the Base Rate: Its the law! by Christoph Engel http://www.coll.mpg.de/pdf_dat/2012_23online.pdf
  21. 21.0 21.1 FORENSICS: Examining the Evidence
  22. Policing and Prosecuting Sexual Assault in Los Angeles City and County page 49
  23. 23.0 23.1 Common Data Fallacies by KDNuggets
  24. 24.00 24.01 24.02 24.03 24.04 24.05 24.06 24.07 24.08 24.09 24.10 24.11 24.12 24.13 24.14 24.15 24.16 Stanford Encyclopedia of Philosophy
  25. 25.0 25.1 25.2 Causal Reasoning iSTAR Assessment: Inquiry for Scientific Thinking and Reasoning, filed in Dimensions of Scientific Reasoning on Apr.11, 2011
  26. 26.0 26.1 26.2 26.3 [http://yandoo.wordpress.com/2015/08/14/false-equivalence/
  27. 27.0 27.1 27.2 http://www.webpages.uidaho.edu/~morourke/404-phil/Summer-99/Lecture%20Notes/4.htm