Logically Fallacious: The Ultimate Collection of Over 300 Logical Fallacies (Academic Edition) (Dr. Bo's Critical Thinking Series)

by Bo Bennett

Disjunction Fallacy Description: Similar to the conjunction fallacy, the disjunction fallacy occurs when one estimates a disjunctive statement (this or that) to be less probable than at least one of its component statements. Logical Forms: Disjunction X or Y (both taken together) is less likely than a constituent Y. Example #1: Mr. Pius goes to church every Sunday. He gets most of his information about religion from church and does not really read the Bible too much. Mr. Pius has a figurine of St. Mary at home. Last year, when he went to Rome, he toured the Vatican. From this information, Mr. Pius is more likely to be Catholic than a Catholic or a Muslim. Explanation: This is incorrect. While it is very likely that Mr. Pius is Catholic based on the information, it is more likely that he is Catholic or Muslim.

Ecological Fallacy (also known as: ecological inference fallacy) Description: The interpretation of statistical data where inferences about the nature of individuals are deduced from inference for the group to which those individuals belong. Logical Form: Group X has characteristic Y. Person 1 is in group X. Therefore, person 1 has characteristic Y. Example #1: Men score better on math than women do. Jerry is a man. Therefore, Jerry is better at math than Sylvia, who is a woman. Explanation: The fact that men score better on math than women is a group generalization. This does not mean that any individual man will score better than any individual woman on math. Educated guesses could be made if we knew more about the statistics. For example, if we just knew that men scored an average of 8% higher than women, we could not even say that any given man is likely to be better at math than any given woman. This is because there could be what is referred to as an uneven distribution, that is, there could be a small group of women who are really bad at math or a small group of men who are really good at math that throws off the curve.

Exclusive Premises (also known as: fallacy of exclusive premises) Description: A standard form categorical syllogism that has two negative premises either in the form of “no X are Y” or “some X are not Y.” Logical Forms: No X are Y. Some Y are not Z. Therefore, some Z are not X. No X are Y. No Y are Z. Therefore, no Z are X. Example #1: No kangaroos are MMA fighters. Some MMA fighters are not Mormons. Therefore, some Mormons are not kangaroos. Example #2: No animals are insects. Some insects are not dogs. Therefore, some dogs are not animals. Example #3: No animals are insects. No insects are dogs. Therefore, no dogs are animals. Explanation: Remember why fallacies are so dangerous: because they appear to be good reasoning. The conclusion in example #1 makes sense, but it does not follow logically—it is an invalid argument. Based on the first two premises, there is no way logically to deduce that conclusion. Now, look at examples #2 and #3. We use the same logical form of the argument, committing the same fallacy, but by changing the terms it is much more clear that something went wrong somewhere, and it did. This kind of argument, the categorical syllogism, cannot have two negative premises and still be valid.

Extended Analogy Description: Suggesting that because two things are alike in some way and one of those things is like something else, then both things must be like that “something else.” In essence, the ad Hitlerum fallacy is an extended analogy because it is the attempt to associate someone with Hitler’s psychotic behavior by way of a usually much more benign connection. Logical Form: A is like B in some way. C is like B in a different way. Therefore, A is like C. Example #1: Jennie: Anyone who doesn’t have a problem with slaughtering animals for food, should not, in principle, have a problem with an advanced alien race slaughtering us for food. Carl: Fruitarians, the crazy people who won’t eat anything except for fruit that fell from the tree, are also against slaughtering animals for food. Are you crazy like them? Explanation: Although I don’t think I can ever give up delicious chicken, Jennie does make a good point via a valid analogy. Ignoring Carl’s attempt to poison the well by using loaded language he is, by extended analogy, claiming the “craziness” of the fruitarians must be shared by her, as well, since they both are alike because they share a view on using animals for food.

Failure to Elucidate obscurum per obscurius Description: When the definition is made more difficult to understand than the word or concept being defined. Logical Form: Person 1 makes a claim. Person 2 asks for clarification of the claim, or a term being used. Person 1 restates the claim or term in a more confusing way. Example #1: Tracy: I don’t like him because of his aura. TJ: What do you mean by that? Tracy: I mean that he is projecting a field of subtle, luminous radiation that is negative. Explanation: This is such a common fallacy, yet rarely detected as one. Usually, out of fear of embarrassment, we accept confusing definitions as legitimate elucidations, that is, we pretend the term that was defined is now clear to us. What exactly is the field? How is it detected? Are there negative and positive ones? How do we know?

Fake Precision (also known as: over-precision, false precision, misplaced precision, spurious accuracy) Description: Using implausibly precise statistics to give the appearance of truth and certainty, or using a negligible difference in data to draw incorrect inferences. Logical Forms: Statistic X is unnecessarily precise and has probability A of being true. Statistic X is interpreted as having probability A+B as being true. Statistic X represents position A. Statistic Y represents position B. Statistic Y is insignificantly different from statistic X. Position A is seen as significantly different from position B. Example #1: Tour Guide: This fossil right here is 120,000,003 years old. Guest: How do you know that? Tour Guide: Because when I started working here three years ago, the experts did some radiometric dating and told me that it was 120,000,000 years old. Explanation: Although more of a comedy skit than anything else, this demonstrates the fallacious reasoning by the tour guide in her assumption that the dates given to her were precise to the year.

Fallacy of Every and All Description: When an argument contains both universal quantifiers and existential quantifiers (all, some, none, every) with different meanings, and the order of the quantifiers is reversed. This is a specific form of equivocation. Logical Form: Quantifier X then quantifier Y. Therefore, quantifier Y then quantifier X. Example #1: Everyone should do something nice for someone. I am someone, so everyone should do something nice for me! Explanation: We have a reversal of the quantifiers. Everyone (quantifier X) should do something nice for someone (quantifier Y). I am someone (quantifier Y), so everyone (quantifier X) should do something nice for me!

False Dilemma (also known as: all-or-nothing fallacy, false dichotomy [form of], the either-or fallacy, either-or reasoning, fallacy of false choice, fallacy of false alternatives, black-and-white thinking, the fallacy of exhaustive hypotheses, bifurcation, excluded middle, no middle ground, polarization) Description: When only two choices are presented yet more exist, or a spectrum of possible choices exists between two extremes. False dilemmas are usually characterized by “either this or that” language, but can also be characterized by omissions of choices. Another variety is the false trilemma, which is when three choices are presented when more exist. Logical Forms: Either X or Y is true. Either X, Y, or Z is true.

Variation: Staying true to the definitions, the false dilemma is different from the false dichotomy in that a dilemma implies two equally unattractive options whereas a dichotomy generally comprises two opposites. This is a fine point, however, and is generally ignored in common usage.

False Effect Description: Claiming that the cause is true or false based on what we know about the effect in a claim of causality that has not been properly established. The cause is often an implied claim, and it is this claim that is being deemed true or false, right or wrong. Logical Forms: X apparently causes Y. Y is wrong. Therefore, X is wrong. X apparently causes Y. Y is right. Therefore, X is right. Example #1: Mom: Watching TV that close will make you go blind, so move back! Jonny: That is B.S., Mom. Sorry, I am not moving. Explanation: The false effect of watching TV too closely is going blind. For the most part, the threat that you will “ruin” your eyesight is an old wives’ tale. Almost certainly, nobody is going blind from sitting too close unless they ram their eyes into the protruding knobs. Regardless of the false effect (i.e., blindness), watching TV too closely (the cause) has been shown to have some adverse effects on vision, so concluding that one shouldn’t “move back” from sitting too close is fallacious. Example #2: The Church used to claim that giving 10% of your income to the Church will free a child’s soul from Limbo into Heaven, so clearly giving money to the Church is a scam! Explanation: Centuries ago, the Church did accept “contributions” to get loved ones out of “Limbo,” and it wasn’t until 2007 when the Church made it clear that Limbo was a theory and not an official doctrine of the Church, separating the Church from that belief. As for the ...

False Equivalence Description: An argument or claim in which two completely opposing arguments appear to be logically equivalent when in fact they are not. The confusion is often due to one shared characteristic between two or more items of comparison in the argument that is way off in the order of magnitude, oversimplified, or just that important additional factors have been ignored. Logical Form: Thing 1 and thing 2 both share characteristic A. Therefore, things 1 and 2 are equal. Example #1: President Petutti ordered a military strike that killed many civilians. He is no different than any other mass murder and he belongs in prison!

Fantasy Projection Description: Confusing subjective experiences, usually very emotionally charged, with objective reality, then suggesting or demanding that others accept the subjective experience as objective reality. New Terminology: In this context, subjective experience is the way one interprets some external stimuli. Objective reality is independent of our interpretations; it is a collection of facts about the world we all share. Logical Form: Person 1 has subjective experience X. Person 1 incorrectly believes that experience X represents objective reality. Therefore, person 1 insists that others accept that X represents objective reality. Example #1: Freddie: People are mean to me wherever I go. It is clear that we live in a cruel world with people who are mostly nasty. If you don’t see that, something is wrong with you!

Far-Fetched Hypothesis Description: Offering a bizarre (far-fetched) hypothesis as the correct explanation without first ruling out more mundane explanations. Logical Form: Far-fetched hypothesis is proposed. Mundane, probable hypotheses are ignored. Example #1: Seth: How did my keys get in your coat pocket? Terrence: Honestly, I don’t know, but I have a theory. Last night, a unicorn was walking through the neighborhood. The local leprechauns did not like this intrusion, so they dispatched the fairies to make the unicorn go away. The fairies took your keys and dropped them on the unicorn, scaring the unicorn back from where he came. The fairies then returned your keys but accidentally put them in my coat pocket. Explanation: When creating a hypothesis, there are infinite possibilities, but far fewer probabilities. Skipping over the probabilities is fallacious reasoning. We should start with the fact that Terrence is lying, then go from there. There are many theories between lying and the mythical creature caper theory.

The Principle of Parsimony states that the most acceptable explanation of an occurrence, phenomenon, or event is the simplest, involving the fewest entities, assumptions, or changes.

Faulty Comparison (also known as: bad comparison, false comparison, inconsistent comparison [form of]) Description: Comparing one thing to another that is really not related, in order to make one thing look more or less desirable than it really is. Logical Form: X is different from Y in way Z. It is unreasonable to compare X to Y in way Z. Therefore, X is seen as more/less favorable. Example #1: Broccoli has significantly less fat than the leading candy bar! Explanation: While both broccoli and candy bars can be considered snacks, comparing the two in terms of fat content and ignoring the significant difference in taste, leads to the false comparison. Example #2: Religion may have been wrong about a few things, but science has been wrong about many more things! Explanation: We are comparing a method of knowledge (science) to a system of belief (faith), which is not known for revising itself based on new evidence. Even when it does, the “wrongs” are blamed on human interpretation. Science is all about improving ideas to get closer to the truth, and, in some cases, completely throwing out theories that have been proven wrong. Furthermore, the claims of religion are virtually all unfalsifiable, thus cannot be proven wrong. Therefore, comparing religion and science on the basis of falsifiability is a faulty comparison.

Galileo Fallacy (also known as: Galileo argument, Galileo defense, Galileo gambit, Galileo wannabe) Description: The claim that because an idea is forbidden, prosecuted, detested, or otherwise mocked, it must be true, or should be given more credibility. This originates from Galileo Galilei’s famous persecution by the Roman Catholic Church for his defense of heliocentrism when the commonly accepted belief at the time was an earth-centered universe. Logical Form: Claim X is made. Claim X is ridiculous. Person A argues that claim Y was seen as ridiculous at the time, and it turned out to be right. Therefore, claim X is true (or should be given more credibility).

Remember that considering the source is often a useful heuristic in quickly assessing if the claim is probably true or not, but dismissing the claim or accepting it as true based on the source is fallacious.

Hasty Generalization (also known as: argument from small numbers, statistics of small numbers, insufficient statistics, argument by generalization, faulty generalization, hasty induction, inductive generalization, insufficient sample, lonely fact fallacy, over generality, overgeneralization, unrepresentative sample) Description: Drawing a conclusion based on a small sample size, rather than looking at statistics that are much more in line with the typical or average situation. Logical Form: Sample S is taken from population P. Sample S is a very small part of population P. Conclusion C is drawn from sample S and applied to population P. Example #1: My father smoked four packs of cigarettes a day since age fourteen and lived until age sixty-nine. Therefore, smoking really can’t be that bad for you. Explanation: It is extremely unreasonable (and dangerous) to draw a universal conclusion about the health risks of smoking by the case study of one man. Example #2: Four out of five dentists recommend Happy Glossy Smiley toothpaste brand. Therefore, it must be great. Explanation: It turns out that only five dentists were actually asked. When a random sampling of 1000 dentists was polled, only 20% actually recommended the brand. The four out of five result was not necessarily a biased sample or a dishonest survey; it just happened to be a statistical anomaly common among small samples.

Hedging Description: Refining your claim simply to avoid counter evidence and then acting as if your revised claim is the same as the original. Logical Form: Claim X is made. Claim X is refuted. Claim Y is then made and is made to be the same as claim X when it is not. Example #1: Freddie: All women are evil, manipulative, man-haters. Wade: Including your mother and best friend? Freddie: Not them, but all the others. Wade: How can you say that, when you only know maybe a hundred or so women? Freddie: Obviously, I am talking about the ones I know. Explanation: The claim changed quite drastically from about 3.5 billion women to about 100, yet there was no admission by Freddie of this drastic change in his argument. Freddie is guilty of committing this fallacy, and those who see Freddie’s initial argument as still valid, are guilty, as well.

Homunculus Fallacy (also known as: homunculus argument, infinite regress) Description: An argument that accounts for a phenomenon in terms of the very phenomenon that it is supposed to explain, which results in an infinite regress. Logical Form: Phenomenon X needs to be explained. Reason Y is given. Reason Y depends on phenomenon X. Example #1: Bert: How do eyes project an image to your brain? Ernie: Think of it as a little guy in your brain watching the movie projected by your eyes. Bert: Ok, but what is happening in the little guy in your head’s brain? Ernie: Well, think of it as a little guy in his brain watching a movie... Explanation: This fallacy creates an endless loop that actually explains nothing. It is fallacious reasoning to accept an explanation that creates this kind of endless loop that lacks any explanatory value.

Hypnotic Bait and Switch Description: Stating several uncontroversially true statements in succession, followed by a claim that the arguer wants the audience to accept as true. This is a propaganda technique, but also a fallacy when the audience lends more credibility to the last claim because it was preceded by true statements. The negative can also be used in the same way. This is a classic sales technique often referred to as, “getting the customer used to saying ‘yes’!” Logical Forms: A succession of uncontroversial true claims is made. Therefore, claim X (which is controversial), is true. A succession of uncontroversial false claims is made. Therefore, claim X (which is controversial), is false. Example #1: Do you love your country? Do you love your family? Do you care about their wellbeing? Then you would love Eatme ice-cream! Example #2: Is it right that such a small percentage of Americans control the vast majority of wealth? Is it right that you have to work overtime just to make ends meet? Is it right that you can’t even afford to leave the state for vacation? Do you really want to vote for Reggie Lipshitz?

Identity Fallacy (also known as: identity politics) Description: When one’s argument is evaluated based on their physical or social identity, i.e., their social class, generation, ethnic group, gender or sexual orientation, profession, occupation or subgroup when the strength of the argument is independent of identity. Logical Form: Person 1 makes argument X. Person 2 dismisses argument X because of the physical or social identity of person 1. Example #1: S.J. Sam: Asian people in this country are systematically passed over in the tech field for non-Asians. Cindy: Actually, according to most research, employers are biased in favor of Asian technical workers. S.J. Sam: Unless you are Asian, keep your mouth shut. You can’t possibly know the struggles of the Asian community!

Illicit Contraposition New Terminology: Illicit: Forbidden by the rules, or in our cases, by the laws of logic. Contraposition: Switching the subject and predicate terms of a categorical proposition, and negating each. Description: A formal fallacy where switching the subject and predicate terms of a categorical proposition, then negating each, results in an invalid argument form. The examples below make this more clear. This is a fallacy only for type “E” and type “I” forms, or forms using the words “no” and “some,” respectively. Logical Forms: No S are P. Therefore, no non-P are non-S. Some S are P. Therefore, some non-P are non-S. Example #1: No Catholics are Jews. Therefore, no non-Jews are non-Catholics. (contraposition) Explanation: By definition, no Catholics are Jews (using type “E” form here)—clear enough. Now let’s take the contraposition of that proposition by switching the placement of “Catholics” and “Jews,” and negating each, and we can see we have a false proposition. “No non-Jews are non-Catholics” clearly does not mean the same thing as “No Catholics are Jews.” In this example, the premise is true but the conclusion is false (I am a non-Jew and a non-Catholic, and statistically speaking, you probably are too.) Example #2: Some dogs bark. Therefore, some non-barking things are non-dogs. (contraposition) Explanation: We now see the type “I” form in action, stating, “Some” dogs bark. This is true, but that really does not matter in determining what form of ...

Inflation of Conflict Description: Reasoning that because authorities cannot agree precisely on an issue, no conclusions can be reached at all, and minimizing the credibility of the authorities, as a result. This is a form of black and white thinking—either we know the exact truth, or we know nothing at all. Logical Form: Authority A disagrees with authority B on issue X. Therefore, we can say nothing meaningful about issue X. Example #1: My mom says that I should study for at least 2 hours each night, and my dad says just a half hour should be fine. Neither one of them knows what they are talking about, so I should just skip studying altogether. Explanation: A disagreement among experts does not mean that both are wrong, the answer is a compromise, or that there is no answer to be known; it simply means that there is disagreement—that is all we can infer. Example #2: Scientists cannot agree on the age of the universe. Some say it is 13.7 billion years old, some say it is only about 13 billion years old. That’s a difference of almost a billion years! It should be clear that because there is so much disagreement, then the 6000-year-old universe should be carefully considered, as well.

Insignificant Cause (also known as: fallacy of insignificant, genuine but insignificant cause, insufficient cause) Description: An explanation that posits one minor factor, out of several that contributed, as its sole cause. This fallacy also occurs when an explanation is requested, and the one that is given is not sufficient to entirely explain the incident yet it is passed off as if it is sufficient. Logical Form: Factors A, B, and C caused X. Factor A, the least significant factor, is said to have caused X. Example #1: Billy murdered all those people because I spanked him when he was a child. Explanation: Assuming that spanking did contribute to Billy’s murderous behavior as an adult (which is a very weak assumption), to sell that as the cause is extremely fallacious. Example #2: The reason Donald Trump got elected was because liberals took political correctness too far. Explanation: Assuming liberals did take political correctness too far, and this did have some effect on voters in favor of Donald Trump, it is unreasonable to claim that this was “the reason” for his win. Exception: Very often causes can be “insignificant” in that they don’t seem meaningful enough considering the meaning of the cause. This is one of the prime drivers of the conspiracy theory fallacy. For example, a lone gunman seems like an insignificant cause in the death of John F. Kennedy. This is our bias at work where we want significant causes for significant effects. “Insignificant,” in the conte...

Just In Case Fallacy (also known as: worst case scenario fallacy) Description: Making an argument based on the worst-case scenario rather than the most probable scenario, allowing fear to prevail over reason. Logical Form: It would be a good idea to accept claim X since it is possible for event Y. Example #1: Maury, you should really wear a helmet when playing chess. You can easily get excited, fall off your chair, and crack your head open.

Least Plausible Hypothesis Description: Choosing more unreasonable explanations for phenomena over more defensible ones. In judging the validity of hypotheses or conclusions from observation, the scientific method relies upon the Principle of Parsimony, also known as Occam’s Razor, which states, all things being equal, the simplest explanation of a phenomenon that requires the fewest assumptions is the preferred explanation until it can be disproved.

Limited Scope Description: The theory doesn’t explain anything other than the phenomenon it explains (that one thing), and at best, is likely to be incomplete. This is often done by just redefining a term or phrase rather than explaining it. Logical Form: Theory X is proposed to explain Y. Theory X explains nothing else but Y. Example #1: My car broke down because it is no longer working. Explanation: “It isn’t working” is just another way of saying “broke down,” and fails to explain why it broke down. Example #2: People often make hasty decisions because they don’t take enough time to consider their choices. Explanation: Not taking enough time to consider choices is precisely what a hasty decision is. Again, no explanation is offered, just a definition in place of an explanation.

Logic Chopping (also known as: quibbling, nit-picking, smokescreen, splitting-hairs, trivial objections) Description: Using the technical tools of logic in an unhelpful and pedantic manner by focusing on trivial details instead of directly addressing the main issue in dispute. Irrelevant over precision. Pay close attention to this fallacy, because after reading this book, you may find yourself committing this fallacy more than any others, and certainly more often than you did before reading this book. Logical Form: A claim is made. An objection is made regarding a trivial part of the claim, distracting from the main point. Example #1: John: Can you please help me push my car to the side of the road until the tow truck comes? Paul: Why push it to the side of the road? Why not just leave it? John: It is slowing down traffic unnecessarily where it is. Paul: Many things slow down traffic—do you feel you need to do something about all them? John: No, but this was my fault. Paul: Was it really? Were you the direct cause of your car breaking down? John: Are you going to help me move this damn car or not?! Explanation: You can see here that Paul is avoiding the request for assistance by attempting to make a deep philosophical issue out of a simple request. While Paul may have some good points, not every situation in life calls for deep critical thought. This situation being one of them.

Missing Data Fallacy (also known as: missing information fallacy) Description: Refusing to admit ignorance to the hypothesis and/or the conclusion, but insisting that your ignorance has to do with missing data that validate both the hypothesis and conclusion. Logical Form: Hypothesis H is put forward. Fatal Flaw F is pointed out. Rather than change the hypothesis to match the data, it is simply assumed that there must be data missing that will eliminate flaw F.

Moralistic Fallacy (also known as: moral fallacy) Description: When the conclusion expresses what is, based only on what one believes ought to be, or what isn’t is based on what one believes ought not to be. This is the opposite of the naturalistic fallacy. In his 1957 paper, Edward C. Moore defined the moralistic fallacy as the assertion that moral judgments are of a different order from factual judgements. Over the years, this concept has been simplified to deriving an “is” from an “ought.” Logical Forms: X ought to be. Therefore, X is. X ought not to be. Therefore, X is not. Example #1: Adultery, as well as philandering, is wrong. Therefore, we have no biological tendency for multiple sex partners.

Moving the Goalposts (also known as: gravity game, raising the bar, argument by demanding impossible perfection) Description: Demanding from an interlocutor that he or she address more and more points after the initial counter-argument has been satisfied refusing to concede or accept the interlocutor’s argument. Logical Form: Issue A has been raised, and adequately answered. Issue B is then raised, and adequately answered. ..... Issue Z is then raised, and adequately answered. (despite all issues adequately answered, the interlocutor refuses to conceded or accept the argument. Example #1: Ken: There has to be an objective morality because otherwise terms like “right” and “wrong” would be meaningless since they have no foundation for comparison. Rob: The terms “right” and “wrong” are based on cultural norms, which do have a subjective foundation—one that changes as the moral sphere of the culture changes. The term “heavy” does not have an objective standard, yet we have no problem using that term in a meaningful way. In fact, very few relational terms have any kind of objective foundation. Ken: But without an objective morality, we would all be lost morally as a race. Rob: Many would say that we are. Ken: But how can you say that torturing children for fun is morally acceptable in any situation? Rob: Personally, I wouldn’t, but you are implying that anything that is not objective must necessarily be seen in all possible ways. A feather may not be seen as “heavy” to anyone,...

Naturalistic Fallacy (also known as: is-ought fallacy, arguing from is to ought, is-should fallacy) Description: When the conclusion expresses what ought to be, based only on what is, or what ought not to be, based on what is not. This is very common, and most people never see the problem with these kinds of assertions due to accepted social and moral norms. This bypasses reason and we fail to ask why something that is, ought to be that way. This is the opposite of the moralistic fallacy. A more traditional use of the naturalistic fallacy is committed when one attempts to define “good” as anything other than itself. The philosopher G. E. Moore (1873-1958) argued that it is a mistake to try to define the concept “good” in terms of some natural property (thus, the name “naturalistic”). Defining the concept “good,” Moore argued, is impossible since it is a simple concept; a concept that cannot be defined in terms of any other concept. Not all philosophers agree that this is a fallacy. Some have argued that ethical terms, such as “good” can be defined in nonethical natural terms. They believe that ethical judgments directly follow from facts, i.e., it is possible to argue from a fact to a value. Logical Forms: X is. Therefore, X ought to be. X is not. Therefore, X ought not to be. Example #1: Homosexuality is / ought to be morally wrong (moral property) because it is not normal (natural property). or Homosexuality is not normal (natural property); therefore, it is / ought to...

Remember, a valid, non-fallacious formal argument does not have to have a true conclusion, it just needs to be truth-preserving—in the case that the premises are all true.

Nirvana Fallacy (also known as: perfect solution fallacy, perfectionist fallacy) Description: Comparing a realistic solution with an idealized one, and discounting or even dismissing the realistic solution as a result of comparing to a “perfect world” or impossible standard, ignoring the fact that improvements are often good enough reason. Logical Form: X is what we have. Y is the perfect situation. Therefore, X is not good enough. Example #1: What’s the point of making drinking illegal under the age of 21? Kids still manage to get alcohol.

No True Scotsman (also known as: appeal to purity [form of], no true Christian, no true crossover fallacy [form of]) Description: When a universal (“all,” “every,” etc.) claim is refuted, rather than conceding the point or meaningfully revising the claim, the claim is altered by going from universal to specific, and failing to give any objective criteria for the specificity. Logical Form: All X are Y. (the claim that all X are Y is clearly refuted) Then all true X are Y. Example #1: In 2011, Christian broadcaster, Harold Camping, (once again) predicted the end of the world via Jesus, and managed to get many Christians to join his alarmist campaign. During this time, and especially after the Armageddon date had passed, many Christian groups publicly declared that Camping is not a “true Christian.” On a personal note, I think Camping was and is as much of a Christian as any other self-proclaimed Christian and religious/political/ethical beliefs aside, I give him credit for having the cojones to make a falsifiable claim about his religious beliefs. Example #2: John: Members of the UbaTuba White Men’s Club are upstanding citizens of the community. Marvin: Then why are there so many of these members in jail? John: They were never true UbaTuba White Men’s Club members. Marvin: What’s a true UbaTuba White Men’s Club member? John: Those who don’t go to jail.

Variations: The more generic appeal to purity can be seen when the claim is that someone “does not have enough of” something, which is why they are not meeting the condition. For example, “If you have the desire for success, you will succeed!” Billy has the desire but is not succeeding. Therefore, Billy’s desire is not strong (or pure) enough. The difference between the appeal to purity and the no true Scotsman is one of degree versus authenticity.

Non Sequitur (also known as: derailment, “that does not follow,” irrelevant reason, invalid inference, non-support, argument by scenario [form of], false premise [form of], questionable premise [form of]) Description: When the conclusion does not follow from the premises. In more informal reasoning, it can be when what is presented as evidence or reason is irrelevant or adds very little support to the conclusion. Logical Form: Claim A is made. Evidence is presented for claim A. Therefore, claim C is true. Example #1: People generally like to walk on the beach. Beaches have sand. Therefore, having sand floors in homes would be a great idea!

Variation: A variation of this fallacy is overextended outrage. Essentially, this is like picking the nuts for the purpose of expressing or inciting outrage toward an entire group.

Oversimplified Cause Fallacy Description: When a contributing factor is assumed to be the cause, or when a complex array of causal factors is reduced to a single cause. It is a form of simplistic thinking that implies something is either a cause, or it is not. It overlooks the important fact that, especially when referring to human behavior, causes are very complex and multi-dimensional. Logical Form: X is a contributing factor to Y. X and Y are present. Therefore, to remove Y, remove X. Example #1: Lead poisoning can contribute to violent behavior. Many inner city children have dangerous levels of lead in their blood. Therefore, violent crime in the inner city can be solved by curing the lead problem. Explanation: We already established that lead poisoning can contribute to violent behavior (note the probabilistic language). This means that there is some unspecified chance. We are taking an unreasonable leap in suggesting that violent crime can be solved (binary language) by curing the lead problem. And, in case you missed it, there is question begging here in assuming that violent behavior leads to violent crime.

Overwhelming Exception Description: A generalization that is technically accurate, but has one or more qualifications which eliminate so many cases that the resulting argument is significantly weaker than the arguer implies. In many cases, the listed exceptions are given in place of evidence or support for the claim, not in addition to evidence or support for the claim. Logical Form: Claim A is made. Numerous exceptions to claim A are made. Therefore, claim A is true. Example #1: Besides charities, comfort, community cohesion, rehabilitation, and helping children learn values, religion poisons everything. Explanation: Besides being a self-refuting statement, the listing of the ways religion does not poison everything, is a clear indicator that the claim is false, or at best, very weak.

Post-Designation (also known as: fishing for data) Description: Drawing a conclusion from correlations observed in a given sample, but only after the sample has already been drawn, and without declaring in advance what correlations the experimenter was expecting to find. Logical Form: A sample from a dataset is drawn. A correlation is found that was not looked at nor is it statistically surprising. The correlation is seen as being meaningful. Example #1: In looking at the records of my students, I have found that 9 out of 10 are an only child. Therefore, society is moving towards one-child families. Explanation: When you start looking at data with no expectations, anything goes, and any data due to random, statistical anomalies will stand out as “odd.” In this case, the fact that 9 out of 10 kids don’t have siblings is outside of the norm, but that is the nature of probability. If you were hypothesizing that most kids don’t have siblings, and you found this data, then it would provide more of a reason to do further research in making a more justified conclusion.

Pragmatic Fallacy Description: Claiming that something is true because the person making the claim has experienced, or is referring to someone who has experienced, some practical benefit from believing the thing to be true. The practical benefit is often summarized as “it works.” The person is confusing the truth-value of the claim with the results from believing the claim to be true. Logical Form: I believe X is true. Believing in X results in practical benefit Y. Therefore, X is true. Example #1: Starbeam: Of course, astrology is true! Nate: How do you know this? Starbeam: Because on the days I forget to consult my horoscope, things always go wrong.

Tip: Don’t underestimate the power of the placebo, especially when it comes to pain management. The mind is very powerful, and if it can trick you into thinking a cheap and harmless placebo improves your overall well-being, let it.

Proof Surrogate Description: A claim masquerading as proof or evidence, when no such proof or evidence is actually being offered. Logical Form: Claim X is made. Claim X is expressed in such a way where no evidence is forthcoming, or no requests for evidence are welcome. Therefore, X is true. Example #1: Jose writes that “people are mostly good at heart.” The author is simply wrong. Explanation: The arguer states that the author is “simply wrong” yet offers no reasons. Words and phrases such as “simply,” “obviously,” “without question,” etc., are indicators that no such evidence will be presented. Example #2: Politician X is crooked—this is an indisputable fact known by everyone except politician X’s supporters. Explanation: The language “this in an indisputable fact” is a surrogate for the evidence showing that politician X is crooked.

Proving Non-Existence Description: Demanding that one proves the non-existence of something in place of providing adequate evidence for the existence of that something. Although it may be possible to prove non-existence in special situations, such as showing that a container does not contain certain items, one cannot prove universal or absolute non-existence. Logical Form: I cannot prove that X exists, so you prove that it doesn’t. If you can’t, X exists. Example #1: God exists. Until you can prove otherwise, I will continue to believe that he does. Explanation: There may be decent reasons to believe in the existence of God, but, “because the existence of God cannot be disproven,” is not one of them. Example #2: Sheila: I know Elvis’ ghost is visiting me in my dreams. Ron: Yeah, I don’t think that really is his ghost. Sheila: Prove that it’s not! Explanation: Once again we are dealing with confusion of probability and possibility. The inability to, “prove,” in any sense of the word, that the ghost of Elvis is not visiting Sheila in her dreams is an impossible request because there is no test that proves the existence and presence of a ghost, so no way to prove the negative or the non-existence. It is up to Sheila to provide proof of this claim, or at least acknowledge that actually being visited by Elvis’ ghost is just a possibility, no matter how slim that possibility is. Exception: If Ron were to say, “That is impossible,” “there is no way you are being visited,” or mak...

Regression Fallacy (also known as: regressive fallacy) Description: Ascribing a cause where none exists in situations where natural fluctuations exist while failing to account for these natural fluctuations. Logical Form: B occurred after A (although B naturally fluctuates). Therefore, A caused B. Example #1: I had a real bad headache, then saw my doctor. Just by talking with him, my headache started to subside, and I was all better the next day. It was well worth the $200 visit fee. Explanation: Headaches are a part of life, and naturally come and go on their own with varying degrees of pain. They regress to the mean on their own, the “mean” being a normal state of no pain, with or without medical or chemical intervention. Had the person seen a gynecologist instead, the headache would have still subsided, and it would have been a much more interesting visit—especially if he were a man. Example #2: After surgery, my wife was not doing too well—she was in a lot of pain. I bought these magnetic wristbands that align with the body’s natural vibrations to reduce the pain, and sure enough, a few days later the pain subsided! Thank you magic wristbands!

Holding beliefs that are unfalsifiable is not fallacious, especially when stated as beliefs or opinions. This becomes fallacious when an unfalsifiable claim is presented as evidence in argumentation.

Shifting of the Burden of Proof onus probandi (also known as: burden of proof [general concept], burden of proof fallacy, misplaced burden of proof, shifting the burden of proof) Description: Making a claim that needs justification, then demanding that the interlocutor justifies the opposite of the claim. The burden of proof is a legal and philosophical concept with differences in each domain. In everyday debate, the burden of proof typically lies with the person making the claim, but it can also lie with the person denying a well-established fact or theory. Like other non-black and white issues, there are instances where this is clearly fallacious, and those which are not as clear. Logical Form: Person 1 is claiming Y, which requires justification. Person 1 demands that person 2 justify the opposite of Y. Person 2 refuses or is unable to comply. Therefore, Y is true. Example #1: Jack: I have tiny, invisible unicorns living in my anus. Nick: How do you figure? Jack: Can you prove that I don’t? Nick: No. Jack: Then I do. Explanation: Jack made a claim that requires justification. Nick asked for the evidence, but Jack shifted the burden of proof to Nick. When Nick was unable to refute Jack’s (unfalsifiable) claim, Jack claimed victory.

Shoehorning Description: The process of force-fitting some current affair into one’s personal, political, or religious agenda. Many people aren’t aware of how easy it is to make something look like confirmation of a claim after the fact, especially if the source of the confirmation is something in which they already believe, like Biblical prophecies, psychic predictions, astrological horoscopes, fortune cookies, and more. Logical Form: Current event X is said to relate to agenda Y. Agenda Y has no rational connection to current event X. Example #1: This example is taken from the Skeptic’s Dictionary (http://www.skepdic.com/shoehorning.html). After the terrorist attacks on the World Trade Center and the Pentagon on September 11, 2001, fundamentalist Christian evangelists Jerry Falwell and Pat Robertson shoehorned the events to their agenda. They claimed, “liberal civil liberties groups, feminists, homosexuals and abortion rights supporters bear partial responsibility...because their actions have turned God’s anger against America.” According to Falwell, God allowed “the enemies of America...to give us probably what we deserve.” Robertson agreed. The American Civil Liberties Union has “got to take a lot of blame for this,” said Falwell and Robertson agreed. Federal courts bear part of the blame, too, said Falwell, because they’ve been “throwing God out of the public square.” Also, “abortionists have got to bear some burden for this because God will not be mocked,” said Falw...