List of Logical Fallacies

What is Abusive Analogy?

The fallacy of abusive analogy is a highly specialized version of the ad hominem argument. Instead of the arguer being insulted directly, an analogy is drawn which is calculated to bring him into scor…

What is Accent?

The fallacy of accent depends for its effectiveness on the fact that the meaning of statements can change, depending on the stress put on the words. The accenting of certain words or phrases can give …

What is Accident?

The fallacy of accident supposes that the freak features of an exceptional case are enough to justify rejection of a general rule. The features in question may be ‘accidental’, having no b…

What is Affirming the Consequent?

To those who confuse hopelessly the order of horses and carts, affirming the consequent is a fallacy which comes naturally. An occupational hazard of those who engage in conditional arguments, this pa…

What is Amphiboly?

Amphiboly is the fallacy of ambiguous construction. It occurs whenever the whole meaning of a statement can be taken in more than one way, and is usually the fault of careless grammar.   The Duch…

What is Analogical Fallacy?

The analogical fallacy consists of supposing that things which are similar in one respect must be similar in others. It draws a comparison on the basis of what is known, and proceeds to assume that th…

What is Appeal to tradition?

Students of political philosophy recognize in the argumentum ad antiquitam the central core of the arguments of Edmund Burke. Put at its simplest, it is the fallacy of supposing that something is good…

What is Apriorism?

Normally we allow facts to be the test of our principles. When we see what the facts are, we can retain or modify our principles. To start out with principles from the first (o priori) and to use them…

What is Argument to the purse?

The argumentum ad crumenam assumes that money is a measure of rightness, and that those with money are more likely to be correct. ‘If you’re so right, why ain’t you rich?’ is t…

What is Bifurcation?

The presentation of only two alternatives where others exist is called the fallacy of bifurcation. Sometimes known as the ‘black and white’ fallacy, it presents an ‘either/or’ …

What is Blinding with Science?

Science enjoys an enormous prestige because it has got so many things right. In the popular imagination, the dedicated scientist in his white coat is a fount of real knowledge as opposed to mere opini…

What is Circulus In Probando?

Circulus in probando is a specialized and very attractive form of the petitio principii. It consists of using as evidence a fact which is authenticated by the very conclusion it supports. It is thus a…

What is Composition?

The fallacy of composition occurs when it is claimed that what is true for individual members of a class is also true for the class considered as a unit. Some nouns can be taken to refer either to the…

What is Concealed Quantification?

When statements are made about a class, sometimes they are about all of the members of it, sometimes about some of them, and at other times it is not clear which is referred to. The fallacy of conceal…

What is Conclusion which Denies Premises?

The conclusion which denies its premises is one of the ‘oh-dear-l-forgot-what-l-started-to-say’ fallacies. It starts by maintaining that certain things must be true, and ends up with a con…

What is Contradictory Premises?

No matter how good the logic may be, you cannot rely on an argument which has certain falsity built into it. For a sound argument true premises are needed, as well as valid logic. The problem with con…

What is Cum hoc ergo propter hoc?

The cum hoc fallacy assumes that events which occur together are causally connected, and leaves no room either for coincidence, or for the operation of an outside factor which separately influences th…

What is Damning the Alternatives?

In cases where there is a fixed and known set of alternatives, it is legitimate to establish the superiority of one by showing all of the others to be inferior. However, in cases where the alternative…

What is Definitional Retreat?

A definitional retreat takes place when someone changes the meaning of the words in order to deal with an objection raised against the original wording. By changing the meaning, he turns it into a dif…

What is Denying the Antecedent?

As with affirming the consequent, the fallacy of denying the antecedent is for those who do not really care if their brain is going forwards or backwards. It does not admit the possibility that differ…

What is Dicto Simpliciter?

Dicto simpliciter is the fallacy of sweeping generalization. It consists of the application of a broad general rule to an individual case whose special features might make it exceptional. To insist th…

What is Division?

The doppelganger of the fallacy of composition is that of division. When we attribute to the individuals in a group something which is only true of the group as a unit, we fall into the fallacy of div…

What is Emotional Appeals?

It would be a strange world if none of us were influenced by emotions. This influence steps over the boundary into the territory of logical fallacy, however, when it becomes the means of deciding the …

What is Equivocation?

Equivocation means using words ambiguously. Often done with intent to deceive, it can even deceive the perpetrator. The fallacy of equivocation occurs when words are used with more than one meaning, e…

What is Every Schoolboy Knows?

You would be amazed what every schoolboy knows. Anxious to secure acquiescence in their controversial claims, disputants solemnly assure their audiences that every schoolboy knows the truth of what th…

What is Ex-post-facto Statistics?

A statistician has been described as someone who draws a mathematically precise line from an unwarranted assumption to a foregone conclusion. It is not quite as bad as that, but there are innumerable …

What is Exception That Proves The Rule?

Exceptions, of course, disprove rules. Despite this, many people confronted by a counter-example to their claim will dismiss it as ‘the exception that proves the rule’. The fallacy consist…

What is Exclusive Premises?

The standard three-line argument called a syllogism has two premises and a conclusion; the premises are the evidence and the conclusion is deduced from them. If both of the premises are negative, no c…

What is Existential Fallacy?

It is a curious feature of logic that statements which refer to the whole of a class do not actually tell us whether there are any members of that class. All cats are selfish. (This tells us that if t…

What is Extensional Pruning?

We are guilty of extensional pruning if we use words in their commonly accepted meaning, but retreat when challenged into a strictly literal definition. The fallacy becomes possible because there are …

What is False Conversion?

False conversion takes place when we deduce from the fact that all cats are animals the additional information that all animals are cats. The converse of a statement, made by exchanging the subject an…

What is False precision?

False precision is incurred when exact numbers are used for inexact notions. When straightforward statements about experience are decked out in numbers well beyond the accuracy of possible measurement…

What is Gambler’s Fallacy?

Few fallacies are more persistent in gambling circles than the belief that the next toss (or spin, or draw) will somehow be influenced by the last one. Gamblers, and others, are led into this fallacy …

What is Genetic Fallacy?

The genetic fallacy has nothing to do with Darwin or Mendel, but a great deal to do with not liking where an argument comes from. People give less credence to views which emanate from those they detes…

What is Half-Concealed Qualification?

In a half-concealed qualification, the words themselves express a limited claim, but the stress and construction is such that the qualifications are glossed over. Although the limits are stated, the a…

What is Hedging?

Hedging is put around arguments, as it is around fields of crops, to prevent them from being trampled. Hedging in argument means sheltering behind ambiguous meanings so that the sense can be changed l…

What is Hominem (abusive), argumentum ad

If you cannot attack the argument, attack the arguer. While an insult itself is not fallacious, it is if made in a way calculated to undermine an opponent’s argument, and to encourage an audienc…

What is Hominem (circumstantial), argumentum ad?

In the argumentum ad hominem circumstantial, the appeal is to the special circumstances of the person with whom one is arguing. Instead of trying to prove the contention true or false on the evidence,…

What is Ignorantiam, argumentum ad?

Socrates was thought by the oracle to be the wisest man because he alone knew how ignorant he was. The knowledge of ignor-ance might have been good at keeping Socrates modest, but it forms a poor basi…

What is Ignoratio Elenchi?

Ignoratio elenchi is one of the oldest fallacies known to us, being first identified by Aristotle. When someone believes himself to be proving one thing, but succeeds in proving something else instead…

What is Illicit Process fallacy?

There is a rule about arguments which tells us that if a term in the conclusion refers to the whole of its class, then the evidence pointing to that conclusion must also have told us about the whole c…

What is Irrelevant Humour?

The fallacy of irrelevant humour is committed when jocular material irrelevant to the subject under review is introduced in order to divert attention away from the argument.   My opponent’s…

What is Lapidem, argumentum ad?

Bishop Berkeley expressed the view that matter does not exist separately from the perception of it. When Boswell told Dr Johnson that this was an idea impossible to refute, the good doctor’s res…

What is Lazarutn, argumentant ad?

The poor may indeed be blessed; but they are not necessarily right. It is a fallacy to suppose that because someone is poor that they must be sounder or more virtuous than one who is rich. The argumen…

What is Loaded Words?

It is possible to influence the outcome of a judgement by the deliberate use of prejudiced terms. When the words used are calculated to conjure up an attitude more favourable or more hostile than the …

What is Misericordiam, argumentum ad?

While pity is an admirable human quality, it does not provide the best basis for argument. When we turn to pity instead of reasoned discourse to support a particular contention, we commit the argument…

What is Nauseam, argumentum ad?

Simple repetition of a point of view does nothing by way of supplying additional evidence or support. Yet it can erode the critical faculty. There is a completely mistaken supposition that a thing is …

What is Non-anticipation?

The fallacy of non-anticipation consists of supposing that everything worth doing or saying has already been done or said. Any new idea is rejected on the grounds that if it were any good, it would al…

What is Novitam, argumentum ad?

If it is a fallacy to suppose that age is a guide to correctness, it is also fallacious to suppose something to be more right simply because it is new. The argumentum ad novitam makes the mis-take of …

What is Numeram, argumentum ad?

Not many people like to be out on a limb. Many prefer instead the comfort of solid numbers behind them, feeling there is less possibility that so many others could be mistaken. The argumentum ad numer…

What is One-sided Assessment?

Many of the decisions we are called upon to weigh up have both advantages and drawbacks. The fallacy of one-sided assessment is fallen into when only one side of the case is taken into consideration. …

What is Petitio Principii?

The fallacy of petitio principii, otherwise known as ‘begging the question’, occurs whenever use is made in the argument of something which the conclusion seeks to establish. The petitio i…

What is Poisoning the well fallacy?

The most attractive feature of poisoning the well is that the opposition is discredited before they have uttered a single word. At its crudest, the fallacy consists in making unpleasant remarks about …

What is Populum, argumentum ad?

The argumentum ad populum appeals to popular attitudes instead of presenting relevant material. In other words, it is based on prejudice. It exploits the known propensity of people to accept that whic…

What is Positive conclusion from negative premise?

An argument which draws a conclusion from two premises is not allowed to have two negative premises, but it is allowed one, provided the conclusion is also negative. A fallacy is committed whenever a …

What is Post hoc ergo propter hoc?

The Latin translates as ‘after this, therefore on account of this’, and it is the fallacy of supposing that because one event follows another, then the second has been caused by the first.…

What is Quaternio terminorum?

Quaternio terminorum is the fallacy of four terms. The standard three-line argument requires that one term be repeated in the first two lines, and eliminated from the conclusion. This is because it wo…

What is Refuting the example fallacy?

Examples are often adduced in support of an argument. When attention is focused on showing the example to be a false one, but leaving the central thesis unchallenged, the fallacy is known as ‘re…

What is Reification?

The fallacy of reification, also called hypostatization, consists in the supposition that words must denote real things. Because we can admire the redness of a sunset, we must not be led by the existe…

What is Secundum quid?

The fallacy of secundum quid is otherwise known as the hasty generalization. Whenever a generalization is reached on the basis of a very few and possibly unrepresentative cases, the fallacy is committ…

What is Shifting ground fallacy?

People may employ hedging to make their contentions ambiguous, or they may use a definitional retreat to claim that their words meant something else. In the third version of this defensive type of ope…

What is Shifting the burden of proof?

Shifting the burden of proof is a specialized form of the argumentum ad ignorantiam. It consists of putting forward an assert-ion without justification, on the basis that the audience must disprove it…

What is Special pleading fallacy?

Special pleading involves the application of a double standard. Although the normal rules of evidence and argument are applied to other cases, the fallacy of special pleading stipulates that some are …

What is Straw man fallacy?

The straw man of logic does not scare anyone. No self-respecting crow would even rustle a feather at him; he is too easy to knock down. Precisely. The straw man is made incredibly easy to knock down s…

What is Temperantlam, argumentum ad?

If fallacies were assigned to the nations of the world, the argumentum ad temperantlam would be allocated to England. It is the Englishman’s fallacy. The argumentum ad temperantiam suggests that…

What is Thatcher’s blame?

When the round black hat first appeared it was dubbed a bowler. This was because it looked like a bowl, and because it was made by the Bowler brothers. The term ‘Thatcher’s blame’ mi…

What is the Bogus Dilemma?

Quite apart from the casual use of the term to describe a difficult choice, the dilemma is also the name of an intricate argument. In a dilemma, we are told the consequences of alternative actions, an…

What is the Complex Question?

Plurium interrogationum, which translates as ‘of many questions’, is otherwise known as the fallacy of the complex question. When several questions are combined into one, in such a way tha…

What is The red herring?

When the hounds are intent on following a scent of their own choosing, in preference to that selected by the master of the hunt, a red herring is used to effect the transfer. Tied to a length of strin…

What is The Runaway train fallacy?

A runaway train takes you speeding into the distance, but unfortunately does not stop. This means that when you reach your required destination you cannot leave it, but are compelled to be taken furth…

What is The slippery slope fallacy?

Slippery slopes are so tricky to negotiate that even the first timid step upon them sets you sliding all the way to the bottom. No one ever goes up a slippery slope; they are strictly for the descent …

What is The Undistributed middle fallacy?

Classic among schoolboy fallacies is the argument that because all horses have four legs and all dogs have four legs, so all horses are dogs. This is the simplest version of the notorious fallacy of t…

What is Threat of force?

When reason fails you, appeal to the rod. The argumentum ad baculum introduces force as a means of persuasion, and is often resorted to by those who would lose the argument without it.   It would…

What is Trivial objections fallacy?

The problem with trivial objections is that they leave the central thesis largely untouched. It is fallacious to oppose a contention on the basis of minor and incidental aspects, rather than giving an…

What is Tu quoque?

Tu quoque means ‘you also’, and is committed when a case is undermined by the claim that its proponent is himself guilty of what he talks of. It is a change of subject from a claim made by…

What is Unaccepted enthyrnemes fallacy?

An enthymeme is an argument with one of its stages understood rather than stated. This is all right as long as both parties accept the tacit assumption. When the unstated element is not accep-ted, we …

What is Unobtainable perfection fallacy?

When the arguments for and against courses of action are asses-sed, it is important to remember that the choice has to be made from the available alternatives. All of them might be criticized for thei…

What is Verecundiam, argumentum ad?

This is the appeal to false authority. While it is perfectly in order to cite as a supporting witness someone who has specialized knowledge of the field concerned, it is a fallacy to suppose that an e…

What is Wishful thinking fallacy?

While many of us engage quite happily in wishful thinking, we elevate it to the status of a fallacy when we use it in place of argument. If we accept a contention because we would like it to be true, …