Logical Fallacies

FALLACIOUS APPEAL TO THE PEOPLE (Argumentum Ad Populum)

this fallacy is committed when there is an irrelevant appeal to emotion that uses common prejudices and passion in order to gain uncritical acceptance of an argument. This is a rather broad term, and used loosely, it can, in the words of logician Irving Copi, "cover a multitude of the favorite techniques of propagandists, demagogues, and advertisers." Advertisements and political rhetoric focusing on whatever themes are trendy in support of diverse (or even contradictory) causes typify ad populum appeals. However, some often-reoccurring examples are discussed below.

FALSE CAUSE or FAULTY CAUSAL ARGUMENT (Non Causa Pro Causa)

this fallacy occurs when a causal relationship is assumed on too little evidence.

concurrency fallacy (cum hoc ergo propter hoc)

this term is used to describe the fallacy of reasoning that one event is the cause of another merely because they are happening at the same time. For example, current elected government officials will be blamed or praised for prevailing societal conditions during their term of office, with no more evidence than that is happening at the same time. In other words, correlation is mistaken for cause.

NON SEQUITUR

this term means "it does not follow" -- the term used in its broadest sense would include any argument in which the premise, relevant or not, does not establish its conclusion. *It is used here in a narrower sense and could be referred to as "irrelevant reason." This fallacy occurs when an argument's premise is irrelevant to its conclusion (and some other more specific fallacy label does not apply). For example, a student might argue that a term paper received too low a grade when the hours spent typing it is taken into consideration. If the amount of time it took to type the paper is not relevant to grading the paper, the argument is non sequitur.*

*UNCLEAR EVIDENCE*

this type of fallacy occurs when evidence is somehow unclear. Unfamiliar vocabulary, unintelligible speech, unusual usage, etc. might cause this. When evidence is unclear, additional tests of accuracy, relevancy, and sufficiency cannot be applied. Specific fallacies include:

GLITTERING GENERALITIES

vague, richly emotive words, terms, or slogans are used to persuade, but not to provide much real meaning ("Family Values," "Americanism," "Law and Order," "Fiscal Responsibility," "New and Improved," "Luxurious," "Famous Name Brands," etc.) Such terms sound good, but until the user defines them fairly extensively, we cannot be sure exactly what is being advocated.

name calling/labeling (these techniques are sometimes grouped as "invective")

"Name Calling" could be differentiated from the ad hominem fallacy in that perhaps no argument may be attacked at all -- merely an individual, perhaps effectively precluding dealing with relevant issues. For example, Governor George Wallace sometimes made references to the "pointy-headed intellectuals who can't park a bicycle straight." (And recently, most American politicians have striven to avoid being associated with the "L-word" -- Liberal) "Labeling" occurs when such terms are applied to an idea or an argument. Is referring to an argument as "propaganda," "scare tactics," etc., in itself a refutation?

AD HOMINEM ARGUMENT (or "Genetic Fallacy")

"ad hominem" means "to the person." This fallacy is committed whenever, instead of trying to disprove the soundness of an argument, it is attacked only in terms of who *made* the argument. (Such attack may extend to the extremes of "demonization.") Of course, it is sometimes appropriate to assess the credibility of a source in terms of motives or competence. Such an analysis is best made when there is an "appeal to authority" and a claim is argued in terms of who is making it or endorsing it. The ad hominem fallacy occurs when focus on the *source* of an argument diverts attention from evidence and reasoning that can be examined independently.

FAULTY ANALOGY

a faulty analogy is a particularly weak or inappropriate one, which is to say, the cases being compared are different in some way that is critical to the argument. For example, "Gun owners would readily accept registering and licensing their guns: after all, car owners have accepted registering and licensing of their cars." Are the cases alike in all ways critical to the argument including, say, a large militant, influential lobby opposed to registration, etc.? Some analogies don't bear much examination: "Don't expect a criminal to reform: a zebra can't change its stripes." The latter analogy is a figurative analogy. Figurative analogies (also known as metaphors and similes) compare things not in the same class or category -- they are always logically faulty when used as proof. Literal analogies are comparisons within the same class or category, and may be sound (logical) or faulty, depending on whether or not the items being compared are alike in all ways critical to the argument.

HASTY GENERALIZATION (Secundum Quid or "Converse Accident")

a general rule is sometimes formed too quickly. To be a trustworthy generalization, a proposition should be inferred from a sufficient number of typical examples with special regard for negative examples (that is, ones that tend to contradict the general rule being formed). For example, "the governor vetoed the Clean-Air Bill -- he's obviously opposed to environmental legislation." Hasty generalization is sometimes the cause of stereotyping in that experiences with a relative few members of a group cause a generalization about the whole group, e.g., conclusion like "Men are pigs" or "Women are crazy," when based on experience, were probably based on a rather inadequate sample.

EITHER-OR FALLACY (also "False Dichotomy")

although there may be only two (or a few) alternative positions on *some* issues, many offer more possibilities. (This is sometimes called the "black-or-white" fallacy in that shades of gray are not recognized.) For example, a statement like "You are either for us or against us," is usually a fallacy. There are certainly other possibilities than "Liberal vs. Conservative," etc. The "Either-Or" fallacy is an unwarranted limitation by an arguer of alternatives on an issue to two (a "false dichotomy") or a few (e.g., trying to divide all nations into "First World," "Second World," and "Third World" countries), thus denying the listener a critical examination of other possible alternatives.

QUESTIONABLE PREMISE

an argument is made from an unproved premise, e.g., a "health food" store may sell many supplements for which there is no compelling proof of their effectiveness. The term "questionable premise" is used here for very direct examples of faulty assumption. More specialized types follow.

EQUIVOCATION

any critical term in an argument must be used consistently, or the fallacy of equivocation has been committed. A classic example is the following argument: "A fetus is a human being. It is 'human' as opposed to being some other kind of animal tissue. It has a state of existence, or 'being'. It is, therefore, a human being." Obviously, the term "human" and "being" are not being used in the sense of "human being" (person). Logical proof that a fetus is a "human being" must be found in an argument or arguments in which that term in not equivocated.

bandwagon (argument ad numerum)

basically, this argument says that everyone (or at least an impressive number of people) believe it, so you should too. A car may be advertised as the "best-selling," a movie as "breaking all box office records," or a politician might flaunt political poll results. What "everyone else" or many others believe may or may not be relevant.

ad hominem circumstantial

because of an arguer's circumstances or personal stake in the matter, his or her argument is attacked. For example, "Of course Congress says that congressional salaries should be increased; everyone wants to make more money!" This is a fallacious argument if it serves to divert attention away from the arguments and evidence in favor of the pay raise.

*INSUFFICIENT EVIDENCE*

evidence may be clear, accurate, and relevant, but still not enough to establish its conclusion. Some specific fallacies of this type follow.

post hoc fallacy (post hoc ergo propter hoc)

in this false cause fallacy one event is cited as the cause of a subsequent event merely because it happened first. For example, if you knew that the driver in an auto accident had been drinking shortly before the accident, it would be fallacious to argue on this information alone that the drinking caused the accident. Again, correlation is mistaken for cause.

poisoning the well

in this type of ad hominem argument the arguer is attacked even before having a chance to argue. For example, it would be poisoning the well if, when two candidates running for office were debating, one finished his or her speech and then said, "My opponent is about to speak, but I'm sure you won't be influenced by his tendency to distort things."

FALLACIOUS APPEAL TO AUTHORITY (Argumentation Ad Vericundium)

it is fallacious to evoke the name and prestige of a person by citing that person as an authority when the matter in question is *not* that person's field of expertise. For example, athletes or actors will often endorse products in which they have no real expertise. It is fallacious to cite such testimony as proof.

BEGGING THE QUESTION (Petitio Principii)

sometimes this term is used synonymously with questionable premise. (And sometimes is is used to mean, "raises the question.") Here it is the fallacy of using the very conclusion an arguer is trying to prove is also used as a premise to prove it. (Another term for this fallacy is "assuming the conclusion.") In many cases, this would not be as obvious as it sounds because the same concept is expressed in different language in both the premise and the conclusion. (E.g., "The United States has the best medical care in the world because no other country has achieved the quality of care available in this country.") "Question begging language" is a term (or terms) that assumes ("begs") what is to be proven. This can be subtle, e.g., a salesperson refers to a "fine product" before the sales-talk mean to prove that very judgement; the term "criminal" may be used in reference to someone not yet convicted or a crime.

snob appeal

the opposite of Plain Folks, this technique is an appeal to *elitism* and may or may not relate to wealth and power. It plays on popular desire to be more sophisticated or fashionable, to obtain certain status symbols, etc. For example, a wine might be advertised as "only for those with the discriminating palate."

argumentum ad nauseam (argument to the point of disugst; i.e., by repetition)

the technique of persuasion by sheer repetition of an argument is common in marketing and political campaigns.

FALLACIOUS APPEAL TO FORCE (Argumentum Ad Baculum)

this fallacy is committed by using force or the threat of force to cause acceptance of an argument when the disagreement should be decided on other issues. For example, a credit department may argue that you should pay a bill on which you disagree because if you don't, it will be turned over to a collection agency. Even though the "appeal to force" may disregard relevant issues, it is often effective.

ad hominem abusive

this fallacy is committed whenever an arguer attacks the character of an opponent or makes a general assessment of an opponent's political, social, etc., type *instead* of dealing with his/her evidence and reasoning. For example, an arguer might assert that "You can't trust anything a politician says," or attack a proposal because a "liberal," "conservative," "Democrat," "Republican," etc. made it instead of analyzing the proposal itself.

ARGUMENT FROM IGNORANCE (Argument Ad Ignorantium)

this fallacy is committed whenever it is argued that a proposition is true because it has not been proven false, or that it is false simply because it has not been proven true. To argue on such basis is to ignore the possibility of "not yet proven either true *or* false." For example, it would be fallacious to argue that because the existence of ghosts has never been disproved, they do exist. This fallacy becomes especially dangerous when someone is accused of an offense and cannot prove his or her innocence.

FALLACIOUS APPEAL TO PITY (Argumentum Ad Misericordiam)

this fallacy is committed whenever pity is appealed to in order to cause acceptance of an argument that should be decided on other issues. For example, a defense attorney might disregard the question of his or her client's guilt or innocence by instead attempting to arouse sympathy in the minds of the jurors by constantly referring to the client's six children who would be left without a provider if the defendant were jailed. This is not to say that pity is not a legitimate motivation (e.g., in an appeal to give to a charity) only that sometimes there are more relevant concerns.

IRRELEVANT ARGUMENT (Ignoratio Elenchi)

this fallacy is sometimes called "irrelevant conclusion." It is committed when an argument that is presented to support a particular position really supports some other position. The argument may be topically relevant in a general way, but still irrelevant in terms of the argument supporting the specific position it is supposed to support. For example, as mentioned earlier, during the controversy surrounding President Bill Clinton's impeachment, argument about moral, legal and constitutional issues were often confused -- proof that the president did something unethical or even illegal was not always relevant to whether he did something impeachable. This fallacy is the "Red Herring," in which an irrelevant, but compelling (or even inflammatory) topic is used to divert argument from the topic at hand.

STRAWMANSHIP

this fallacy occurs when an opponent's position is misrepresented in order to better attack it, building a "strawman" to knock them down. For example, if someone were an opponent of capital punishment, it would be strawmanship to represent that position as on of "condoning murder." Sometimes termed "distortion," this fallacy is very common during political campaigns.

ACCENT

this fallacy occurs when the meaning of some evidence is distorted by a change in *emphasis*. This can mean anything from a voice inflection to actually leaving out words, or using a statement "out of context" in a way that changes the meaning that would be apparent if the rest of the passage were there. For example, if a movie critic said, "This picture, except for some good music, was an unmitigated disaster," it would be fallacious to cite the critic's opinion only in terms of "...good music" in a movie ad.

tu quoque ("thou also")

this means, roughly, "you're another." This fallacy occurs when an accusation is countered by accusing the accuser of the same thing. For example, a hunter might be attacked as unethical for "killing helpless animals;" he then replies that the accuser is a hypocrite because he or she eats beef, which also comes from "killing helpless animals." All that has been accomplished is the involvement of more dead animals; the original assertion has not been addressed.

plain folks

this technique involves associating a person or idea with the "ordinary" or "common" person, or with the values associated with such people. A politician who seeks election because he or she is "of the people," from a "humble, hard working" background as a farmer, small business owner, etc., is using a "plain folks" appeal.

transfer

this technique is often a very subtle one because no overt argument might be made. Sometimes simply surrounding something with various symbols will cause a "transfer" of positive or negative feelings about one into feelings about the other. (It is often used in conjunction with other techniques mentioned here.) For example, a cigarette ad might show a very masculine man or associate the product with high fashion or the women's movement, or a cosmetic ad may picture a very attractive model. A politician might be surrounded with symbols of traditional values: flags, the presidential seal, etc.

COMPLEX QUESTION (Plurium Interrogationum)

this technique is sometimes referred to as "loaded question." An unproved premise is included in a question. ("Have you stopped beating your wife?") The question form might take the unwarranted assumption less obvious.

*IRRELEVANT EVIDENCE (or IRRELAVENT ARGUMENT)*

this term covers a wide variety of fallacies in which a premise that may seem pertinent but is actually irrelevant is used to prove a conclusion (or an entire argument, sound in itself, may be used to support a position to which it is irrelevant). It should be remembered about this category of fallacies that what is relevant *depends largely on context*. Some typical abuses are described below.

*INNACURATE (or questionable) EVIDENCE*

this type of fallacy involves use of a premise (evidence) that is untrue, or at least requires further proof. It might be an unwarranted assumption that is then used to prove a questionable (at least questionable) conclusion. However, we may not think to examine the original assumption -- it is often not even directly stated. The outright lie fits in this category; so does "BS," more polite usage for what philosopher Harry M. Frankfurt defines as claims that are not outright lies, but are made without concern about whether they are true or not.

CIRCULAR ARGUMENT (Circulus in Probando)

two unproved propositions are used to prove each other as in, "Marijuana should be outlawed because it's harmful; we know it is harmful because it was outlawed."

OVERGENERALIZATION (Dicto Simplicitor or "Accident")

what is true "in general" may not be true in every case. An overgeneralization would occur if you were to apply such a general rule to a specific case when, in fact, there are exceptional or "accidental" circumstances that prevent the general rule from applying. For example, given that African-American voters tend to vote for Democratic candidates, it would be a fallacy to assume that a particular African-American voted for the Democrat, inferred from the voter's ethnicity alone. This demonstrates another aspect of stereotyping: real tendencies of differences between groups may not apply to a given individual.