A List of Fallacies

Have you ever heard an argument that sounds confusing, twisted, or wrong, or maybe the argument contains assumptions that you don’t accept? And maybe you’ve made such arguments yourself, but you can’t quite explain why your argument sounds off.

The following presents some twenty-plus fallacies one might encounter in arguments. Use this list to help you scrub these fallacies from your value propositions, elevator pitches, pitch decks, business plans, etc.

Fallacies

Adapted by Eben Johnson from Logic by Stan Baronett, Oxford Press, 2016; logiccheck.ai (viewed 17 February 2025); and philosophy.lander.edu (viewed 17 February 2025). The Latin translations are from A Dictionary of Latin Words and Phrases by James Morwood; Oxford Press; 1998.

Formal fallacies are logical errors that occur in the form or structure of an argument and are restricted to deductive arguments.

Informal fallacies are mistakes in reasoning that occur in ordinary language and are different from errors in the form or structure of arguments, as found in some deductive arguments.

Deductive arguments are arguments in which, assuming the premises to be true, it is impossible for the conclusion to be false; if yes and yes, then the argument is valid and sound. “A equals B, and B equals C. Therefore, A equals C.”

Inductive arguments are arguments in which, assuming the premises are true, it is improbable that the conclusion is false; if yes and yes, then the argument is strong and cogent. “I’m told this jar contains one blue marble and one hundred red ones. Therefore, assuming my information is correct, if I reach in and draw out one marble, I’ll likely draw a red one.”

A loose mnemonic to help remember deductive versus inductive arguments is to think deductive arguments use data and inductive ones use insight—“d” for data and deductive and “i” for insight and inductive.

Personal Attacks

1. Ad Hominem (L., lit., to the individual man) abusive: An attack on alleged character flaws of a person instead of the person’s argument. “Don’t listen to him. He does drugs.”
2. Ad Hominem (L., lit., to the individual man) circumstantial: When a person’s argument is rejected based on the person’s life circumstances. “His opinions have no merit—his party lost the election.”
3. Poisoning the well: When a person is attacked before presenting their case. “We shouldn’t let her speak. She spent a year in jail.”
4. Tu Quoque (L., lit., you too, you’re another): When one person seeks to avoid the issue by claiming the other is a hypocrite. “You say I should not do drugs, but you did drugs.”

Emotional Appeals

5. Appeal to fear or force: A threat of harmful consequences used to force acceptance of a course of action that would otherwise be unacceptable. “If the workers do not accept a wage cut, the company may close its doors. Thus, the workers should accept a wage cut.”
6. Appeal to nature: When an argument assumes that something natural is therefore beneficial, correct, good, right, or valid; conversely, something unnatural is not beneficial, correct, good, right, or valid. This fallacy derives from the assumption that nature, or what happens in nature, is superior to all unnatural things. “Raw food is natural food; therefore, we should not eat cooked food.”
7. Appeal to the people: When an argument manipulates a psychological need or desire so that a reader or listener will accept the conclusion. “We shouldn’t accept illegal aliens. They broke the law entering our country, so we should not let them murder our children.”
8. Appeal to pity: When an argument relies exclusively on a sense of pity, compassion, or mercy to support a conclusion. “We shouldn’t jail this child. After all, he’s an orphan.”

Weak Inductive Argument Fallacies

9. Biased sample: Use of a non-representative biased sample to support a statistical claim about an entire population. “A sample of one thousand religious people suggested 85% of them believe X is wrong. Therefore, 85% of all Americans believe X is wrong.”
10. Composition: 1) The mistaken transfer of an attribute of the individual parts of an object to the object as a whole. “His body cells are small. Therefore, he must be small.” 2) The mistaken transfer of an attribute of the individual members of a class to the class itself. “A motorcycle is noisier than a car. Therefore, motorcycles contribute more to noise than cars.”
11. Division: 1) The mistaken transfer of an attribute of the object as a whole to individual parts of an object. “The elephant is big. Thus, the elephant must have big cells.” 2) The mistaken transfer of an attribute of a class to individual members of the class. “That is a wooden chair. Thus, its legs must be made of wood.”
12. Hasty generalization: A generalization built on a few instances. “I saw a red car speeding. Probably all drivers of red cars speed.”
13. Post Hoc (L., lit., after this): The mistaken assumption that just because one event occurred before another event, the first event must have caused the second event. (The complete Latin phrase is “post hoc, ergo propter hoc,” meaning “after this, therefore on account of this.”) “I felt sick after eating at that restaurant. Therefore, that restaurant’s food is bad.”
14. Rigid application of a generalization: When a generalization or rule is inappropriately applied to the case at hand (it has no exceptions). “Even though the man rescued a child in danger, I can’t believe the police didn’t arrest him for trespassing.”
15. Slippery slope: An attempt to connect a series of occurrences such that the first link in a chain leads directly to a second link, and so on until a final unwarranted situation is said to be the inevitable result. “If you smoke pot, then you’ll shoot heroin, and then you’ll soon murder people.”

Fallacies of unwarranted assumptions are arguments that assume the truth of some unproven or questionable claim.

16. Appeal to ignorance: An argument built on a position of ignorance. 1) A statement must be true because it has not been proven false. “There’s life beyond Earth because no one has proven there isn’t.” 2) A statement must be false because it has not been proven to be true. “There’s no life beyond Earth because we haven’t received a signal.”
17. Appeal to an unqualified authority: An argument that relies on the opinions of people with no expertise, training, or knowledge of the relevant issue or whose testimony is untrustworthy. “I’m an actor on TV, and what’s going on in country X is wrong.”
18. Begging the question: 1) When a premise is simply reworded in the conclusion. “Pavarotti is the best singer, so no one is better than Pavarotti.” 2) Circular reasoning: A set of statements that seem to support each other with no clear beginning or end. “He never lies, and because he always tells the truth, you should believe him.” 3) The argument contains certain key information that may be controversial or is not supported by the facts. “Murder is always wrong. Therefore, abortion is always wrong.”
19. Complex question: When a single question actually contains multiple parts and an unestablished hidden assumption. “Do you still cheat on your taxes?”
20. Fallacy of accident: When a commonly accepted generalization is improperly used to infer a specific case. “By law, all children must attend school. Your child, although ill, must attend school.”
21. False dichotomy: When it is assumed only two choices are possible when, in fact, other options exist. “We either give up basic freedoms, or we lose the war.”

Fallacies of diversion are when the meaning of terms or phrases is changed within the argument or when our attention is purposely or accidentally diverted from the issue at hand.

22. Equivocation: When the conclusion of an argument relies on a shift in the meaning of a term or phrase in the premises. “He’s an idiot. Since idiots should be kept in hospitals, he should be in a hospital.”
23. Missing the point: When premises that seem to lead logically to one conclusion are used instead to support an unexpected conclusion. “It may take years to solve a crime. Therefore, our police should have the same equipment as our military.”
24. Misleading precision: A claim that appears statistically significant but is not. “Our desert foods contain 30% less fat than our competitor’s, so you should eat our deserts to lose weight.”
25. Red herring: When a person completely ignores an opponent’s position and changes the subject, diverting the discussion in a new direction. “She says, ‘Abusive use of social media has hurt some children,’ and he replies, ‘How can we criticize the use of the internet when it enables families to stay in touch and people to purchase airplane tickets?’”
26. Straw man: When an argument is misrepresented to create a new argument that can be refuted easily. “He says, ‘Intelligent design shouldn’t be taught in science classes,’ and she replies, ‘He’s against teaching intelligent design, but he’s really trying to end religious freedom in our country.’”

A final recommendation: if you and your interlocutor or interlocutors are arguing and seem to be at an impasse, then pause, step back, and together consider each of your enthymemes (loosely, unstated premises). You might discover that your impasse was based on having differing and unstated assumptions, definitions, beliefs, etc. “Oh, wow, I thought x meant y. My mistake.” Or, “Yes, of course, I accept exceptions—I didn’t think I needed to say so. It’s just that . . .”