By accident or design, the trappings of fallacies may exploit emotional triggers in the listener or interlocutor (e.g. Appeal to emotion), or take advantage of social relationships between people (e.g. Appeal to authority). Fallacious arguments are often structured using rhetorical patterns that obscure the logical argument, making fallacies difficult to diagnose. Also, the component parts of the fallacy may be spread out over separate arguments.
오류는 논쟁에 있어서 부정확한 추론에 의해 형성된 잘못된 개념이다.
Material fallacies
The taxonomy of material fallacies is widely adopted by modern logicians and is based on that of Aristotle, Organon (Sophistici elenchi). This taxonomy is as follows:
Fallacy of Accident: a generalization that disregards exceptions
Example
Argument: Cutting people is a crime. Surgeons cut people. Therefore, surgeons are criminals.
Problem: Cutting people is only sometimes a crime.
Argument: It is illegal for a stranger to enter someone's home uninvited. Firefighters enter people's homes uninvited, therefore firefighters are breaking the law.
Problem: The exception does not break nor define the rule.
Also called destroying the exception, a dicto simpliciter ad dictum secundum quid
예외를 무시하고 일반적인 규칙을 이끌어 낸다.
예)
주장: 사람을 칼로 베는 것은 범죄다. 외과 의사는 사람을 칼로 벤다. 따라서 외과 의사는 범죄자다.
문제: 사람을 칼로 벤다 하더라도 죄가 되지 않는 경우도 있다.
주장: 초대받지 않고 모르는 사람의 집에 들어가는 것은 불법이다. 소방관들은 초대받지 않고 다른 사람의 집에 들어간다. 따라서 소방관들은 범법자들이다.
Converse Fallacy of Accident: argues from a special case to a general rule
Example
Argument: Every swan I have seen is white, so it must be true that all swans are white.
Problem: What one has seen is a subset of the entire set. One cannot have seen all swans.
Also called reverse accident, destroying the exception, a dicto secundum quid ad dictum simpliciter
특수한 몇 가지 사례를 가지고 일반적인 규칙을 이끌어 낸다.
예)
주장: 이제까지 내가 만나본 미녀는 모두 잠꾸러기였다. 따라서 미녀는 잠꾸러기다.
문제: 그 사람이 만나본 미녀는 전체 미녀들 중에서 일부분에 지나지 않는다. 그가 만나보지 않은 미녀들 중에는 잠이 없는 사람이 있을 수 있다.
Irrelevant Conclusion: diverts attention away from a fact in dispute rather than address it directly.
Example
Argument: Kim Jong Il believes that war is justifiable therefore it must be justifiable.
Problem: Kim Jong Il can be wrong. (In particular this is an appeal to authority).
Special cases:
purely personal considerations (argumentum ad hominem),
popular sentiment (argumentum ad populum--appeal to the majority; appeal to loyalty.),
fear (argumentum ad baculum),
conventional propriety (argumentum ad verecundiam--appeal to authority)
to arouse pity for getting one's conclusion accepted (argumentum ad misericordiam)
proving the proposition under dispute without any certain proof (argumentum ad ignoratiam)
Also called Ignoratio Elenchi, a "red herring"
Affirming the Consequent: draws a conclusion from premises that do not support that conclusion by assuming Q implies P on the basis that P implies Q
Example:
Argument: If a person runs barefoot, then his feet hurt. Socrates' feet hurt. Therefore, Socrates ran barefoot.
Problem: Other things, such as tight sandals, can result in sore feet.
Argument: If it rains, the ground is wet. The ground is wet, therefore it rained.
Problem: There are other ways by which the ground could get wet (i.e. dew, underground spring, urine etc.).
'P이면 Q이다'를 가지고 'Q이면 P이다'라는 결론을 끌어낸다.
예)
주장: 미녀는 잠꾸러기다. 그녀는 잠이 많다. 따라서 그녀는 미녀다.
문제: 미녀가 아닌 여자도 잠이 많을 수 있다. (물론 위의 주장은 '미녀는 잠꾸러기다'라는 전제부터가 잘못되었다.)
Denying the antecedent: draws a conclusion from premises that do not support that conclusion by assuming Not P implies Not Q on the basis that P implies Q
Example
Argument: If it is raining out, it must be cloudy. It is not raining out. Therefore, it is not cloudy.
Problem: There does not have to be rain to have clouds.
'P이면 Q이다'를 가지고 'P가 아니면 Q가 아니다'라는 결론을 끌어낸다.
예)
주장: 비가 오는 날에는 반드시 하늘에 구름도 끼어 있다. 지금 바깥에 비가 오지 않는다고 한다. 따라서 구름도 끼어있지 않을 것이다.
문제: 구름이 끼어 있다고 해서 반드시 비가 오라는 법은 없다.
Begging the question: demonstrates a conclusion by means of premises that assume that conclusion.
Example
Argument: Billy must be telling the truth, because I have heard him say the same thing many times before.
Problem: Billy may be consistent in what he says, but he may have been lying the whole time.
Argument: The Bible says that God exists and the Bible is always right because it was inspired by God, therefore God exists.
Problem: The premises are circular in nature because each premise is assuming the other.
Also called Petitio Principii, Circulus in Probando, arguing in a circle, assuming the answer. It is worth noting that a circular argument may actually be both logically and factually correct. Circularity itself has no bearing on the truth or falseness of the argument at all, the fallacy is to use a circular argument as a proof of truth.
Fallacy of False Cause or Non Sequitur: incorrectly assumes one thing is the cause of another. Non Sequitur is Latin for "It does not follow."
Example
Argument: Our nation will prevail because God is great.
Problem: There is no necessary cause and effect between God's greatness and a nation prevailing. Simply because God can be considered great does not mean a nation will prevail.
Special cases
post hoc ergo propter hoc: believing that temporal succession implies a causal relation.
Example
Argument: After my son had his vaccine, he developed autism. Therefore, the vaccine caused autism.
Problem: The characteristics of autism may generally become noticeable at the age just following the typical age children receive vaccinations.
cum hoc ergo propter hoc: believing that happenstance implies causal relation (aka as fallacy of causation versus correlation: assumes that correlation implies causation).
Example
Argument: More cows die in India in the summer months. More ice cream is consumed in summer months. Therefore, the consumption of ice cream in the summer months is killing Indian cows.
Problem: It is hotter in the summer, resulting in both the death of cows and the consumption of ice cream.
하나가 다른 것의 원인이 된다고 잘못 가정한다.
예)
주장: 우리나라는 번영을 누릴 것이다. 왜냐하면 신은 위대하기 때문이다.
문제: 신이 위대하다는 것과 한 나라가 번영을 누린다는 것 사이에는 아무런 연관이 없다.
Fallacy of Many Questions: groups more than one question in the form of a single question
Example
Argument: Is it true that you no longer beat your wife?
Problem: A yes or no answer will still be an admission of guilt to beating your wife at some point.
Also called Plurium Interrogationum and other terms
Straw man: A straw man argument is an informal fallacy based on misrepresentation of an opponent's position.
Example
Argument Person A: Sunny days are good.
Argument Person B: If all days were sunny, we'd never have rain, and without rain, we'd have famine and death. You are obviously wrong.
Problem: B has falsely framed A's argument to imply that A says that only sunny days are good, and has argued against that assertion instead of the assertion A has made.
허수아비 잘못
허수아비 잘못은 상대방의 말을 엉뚱하게 해석해 놓고 공격하는 것을 말한다.
예)
주장 A: 맑은 날씨가 좋다.
주장 B: 맑은 날씨는 비가 오지 않는 것이고 비가 오지 않으면 농작물이 자라지 않으며 농작물이 자라지 않으면 우리는 모두 굶어 죽게 된다. 따라서 당신 말은 틀렸다.
문제: B는 A가 맑은 날씨만 좋다고 말한 것으로 멋대로 해석해 놓고 그것에 반박하였다.
Consider the following argument which claims to prove that pie is delicious:
Pie is food.
Food is delicious.
Therefore, pie is delicious.
This particular argument has the form of a categorical syllogism. In this case "Pie is food" and "Food is delicious" act as premises. The first assumption is almost true by definition: pie is a foodstuff edible by humans. The second assumption is less clear; it could mean any one of the following:
All food is delicious.
One particular type of food is delicious.
Most food is delicious.
To me, all food is delicious.
Some food is delicious.
Only the first interpretation validates the second premise. If the interlocutor grants this interpretation then the argument is valid; the interlocutor is essentially conceding the point. However, the interlocutor is more likely to believe that some food is not delicious. In this case, the speaker must prove the assertion that pie is a unique type of universally delicious food. This is a disguised form of the original thesis. In this case, the speaker commits the logical fallacy of begging the question.
파이가 맛있다는 것을 증명하려는 아래의 논쟁을 살펴보자:
"파이는 음식이다."
"음식은 맛있다."
"따라서 파이는 맛있다."
이 논쟁은 삼단논법의 형식을 갖추고 있다. "파이는 음식이다"와 "음식은 맛있다"는 전제의 역할을 한다. 첫 번째 전제는 정의에 의하여 거의 참이다: 파이는 사람이 눈으로 확인할 수 있는 분명한 음식이다. 두 번째 전제는 다소 모호하다; 그것은 아래에 나열한 몇 가지 중의 하나가 될 수 있다:
"모든 음식은 맛있다."
"음식의 한 종류는 맛있다."
"대부분의 음식은 맛있다."
"나에게는 모든 음식이 맛있다."
"어떤 음식은 맛있다."
두 번째 전제의 뜻이 이 중에서 "모든 음식은 맛있다."가 되어야만 위의 삼단논법은 성립한다.
Verbal fallacies
Verbal fallacies are those in which a conclusion is obtained by improper or ambiguous use of words. They are generally classified as follows.
언어적 잘못
언어적 잘못은 부적절하거나 불명확한 용어를 사용하여 얻은 결론을 말한다. 그 예는 다음과 같다.
Equivocation consists in employing the same word in two or more senses, e.g. in a syllogism, the middle term being used in one sense in the major and another in the minor premise, so that in fact there are four not three terms
Example Argument: All heavy things have a great mass; this is heavy fog; therefore this fog has a great mass.
Problem: Heavy describes more than just weight. In the case of fog it means that the fog is dense not that it has a great mass.
중의어 잘못
한 단어는 여러가지 의미를 지니고 있을 때가 많다. 삼단논법에서 첫 번째 전제와 두 번째 전제에 동일한 용어를 사용하면서도 의미는 다르게 사용할 경우 바로 이 오류가 발생한다.
예)
논쟁: 무거운 것은 질량이 많이 나간다. 그 남자는 입이 무겁다. 따라서 그 남자의 입은 질량이 많이 나간다.
문제: '무겁다'는 말은 꼭 '질량이 많이 나간다'는 것을 뜻하지는 않는다. 첫 번째 전제에서는 그런 뜻으로 사용하였지만 두 번째 전제에서는 '불필요한 문제를 일으킬 말은 하지 않는다'는 뜻으로 쓰였다.
Connotation fallacies occur when a dysphemistic word is substituted for the speaker's actual quote and used to discredit the argument. It is a form of attribution fallacy.
Amphibology is the result of ambiguity of grammatical structure
Example: The position of the adverb "only" in the a sentence starting with "He only said that" results in a sentence in which it is uncertain as to which of the other three words the speaker is intending to modify with the adverb.
Fallacy of Composition "From Each to All". Arguing from some property of constituent parts, to the conclusion that the composite item has that property. This can be acceptable (i.e., not a fallacy) with certain arguments such as spatial arguments (e.g. "all the parts of the car are in the garage, therefore the car is in the garage")
Example Argument: All the band members (constituent parts) are highly skilled, therefore the band (composite item) is highly skilled.
Problem: The band members may be skilled musicians but not in the same styles of music.
합치기 잘못
구성요소의 속성을 가지고 전체의 속성을 규정한다.
때로는 구성요소의 속성으로 전체의 속성을 규정하는 것이 맞을 수도 있다. 예를 들면, "그 자동자의 모든 부품은 차고에 있다. 따라서 그 자동차는 차고에 있다."고 할 때 이 말은 성립한다.
예)
주장: 그 비빔밥에 들어간 재료는 모두 맛있는 재료들이다. 따라서 그 비빔밥은 맛있다.
문제: 맛있는 케익과 맛있는 생선회와 맛있는 된장 등을 섞어 만든 비빔밥이 꼭 맛있으리라는 보장은 없다.
Division, the converse of the preceding, arguing from a property of the whole, to each constituent part
Example Argument: "The university (the whole) is 700 years old, therefore, all the staff (each part) are 700 years old".
Problem: Each and every person currently on staff is younger than 200 years. The university continues to exist even when, one by one, each and every person on the original staff leaves and is replaced by a younger person. See Theseus's Ship paradox.
Example Argument: "This cereal is part of a nutritious breakfast therefore the cereal is nutritious."
Problem: Simply because the breakfast taken as a whole is nutritious does not necessarily mean that each part of that breakfast is nutritious.
쪼개기 잘못
전체의 속성을 가지고 구성요소의 속성을 규정한다.
예)
주장: 이 대학은 700년 넘었다. 따라서 이 대학의 교수들은 700살이 넘는다.
Proof by verbosity, sometimes colloquially referred to as argumentum verbosium - a rhetorical technique that tries to persuade by overwhelming those considering an argument with such a volume of material that the argument sounds plausible, superficially appears to be well-researched, and it is so laborious to untangle and check supporting facts that the argument might be allowed to slide by unchallenged.
Accent, which occurs only in speaking and consists of emphasizing the wrong word in a sentence. e.g., "He is a fairly good pianist," according to the emphasis on the words, may imply praise of a beginner's progress, or an expert's deprecation of a popular hero, or it may imply that the person in question is a deplorable pianist.[citation needed]
Figure of Speech, the confusion between the metaphorical and ordinary uses of a word or phrase.
Example: The sailor was at home on the sea.
Problem: The expression 'to be at home' does not literally mean that one's domicile is in that location.
Fallacy of Misplaced Concretion, identified by Whitehead in his discussion of metaphysics, this refers to the reification of concepts which exist only in discourse.
Example 1
Tom argues:
Joe is a good tennis player.
Therefore, Joe is 'good', that is to say a 'morally' good person.
Here the problem is that the word good has different meanings, which is to say that it is an ambiguous word. In the premise, Tom says that Joe is good at some particular activity, in this case tennis. In the conclusion, Tom states that Joe is a morally good person. These are clearly two different senses of the word "good". The premise might be true but the conclusion can still be false: Joe might be the best tennis player in the world but a rotten person morally. However, it is not legitimate to infer he is a bad person on the ground there has been a fallacious argument on the part of Tom. Nothing concerning Joe's moral qualities is to be inferred from the premise. Appropriately, since it plays on an ambiguity, this sort of fallacy is called the fallacy of equivocation, that is, equating two incompatible terms or claims.
Example 2
One posits the argument:
Nothing is better than eternal happiness.
Eating a hamburger is better than nothing.
Therefore, eating a hamburger is better than eternal happiness.
This argument has the appearance of an inference that applies transitivity of the two-placed relation is better than, which in this critique we grant is a valid property. The argument is an example of syntactic ambiguity. In fact, the first premise semantically does not predicate an attribute of the subject, as would for instance the assertion
A potato is better than eternal happiness.
In fact it is semantically equivalent to the following universal quantification:
Everything fails to be better than eternal happiness.
So instantiating this fact with eating a hamburger, it logically follows that
Eating a hamburger fails to be better than eternal happiness.
Note that the premise A hamburger is better than nothing does not provide anything to this argument. This fact really means something such as
Eating a hamburger is better than eating nothing at all.
Thus this is a fallacy of equivocation.
Deductive fallacy
In philosophy, the term logical fallacy properly refers to a formal fallacy: a flaw in the structure of a deductive argument which renders the argument invalid.
However, it is often used more generally in informal discourse to mean an argument which is problematic for any reason, and thus encompasses informal fallacies as well as formal fallacies. – valid but unsound claims or bad nondeductive argumentation – .
The presence of a formal fallacy in a deductive argument does not imply anything about the argument's premises or its conclusion (see fallacy fallacy). Both may actually be true, or even more probable as a result of the argument (e.g. appeal to authority), but the deductive argument is still invalid because the conclusion does not follow from the premises in the manner described. By extension, an argument can contain a formal fallacy even if the argument is not a deductive one; for instance an inductive argument that incorrectly applies principles of probability or causality can be said to commit a formal fallacy.
Formalisms and frameworks used to understand fallacies
A different approach to understanding and classifying fallacies is provided by argumentation theory; see for instance the van Eemeren, Grootendorst reference below. In this approach, an argument is regarded as an interactive protocol between individuals which attempts to resolve a disagreement. The protocol is regulated by certain rules of interaction, and violations of these rules are fallacies. Many of the fallacies in the list below are best understood as being fallacies in this sense.
Other systems of classification
Of other classifications of fallacies in general the most famous are those of Francis Bacon and J. S. Mill. Bacon (Novum Organum, Aph. 33, 38 sqq.) divided fallacies into four Idola (Idols, i.e. False Appearances), which summarize the various kinds of mistakes to which the human intellect is prone. With these should be compared the Offendicula of Roger Bacon, contained in the Opus maius, pt. i. J. S. Mill discussed the subject in book v. of his Logic, and Jeremy Bentham's Book of Fallacies (1824) contains valuable remarks. See Rd. Whateley's Logic, bk. v.; A. de Morgan, Formal Logic (1847) ; A. Sidgwick, Fallacies (1883) and other textbooks.
