Logical Fallacies

Vocabulary flashcards covering key terms and definitions related to formal and informal logical fallacies presented in the lecture notes.

Fallacy

A mistake or error in reasoning.

Formal Fallacy

A structural error in a deductive argument that makes the argument invalid.

Informal Fallacy

An error in reasoning found in the content of an argument, usually in inductive arguments, that requires evaluation to detect.

Inverse Error

A formal fallacy that wrongly infers 'not-Q, therefore not-P' from a conditional 'If P, then Q.'

Converse Error

A formal fallacy that wrongly infers 'Q, therefore P' from a conditional 'If P, then Q.'

Argument ad Ignorantiam (Appeal to Ignorance)

Claiming something is true because it hasn’t been proven false, or false because it hasn’t been proven true.

Argument ad Verecundiam (Appeal to Inappropriate Authority)

Supporting a claim by citing an authority who is not qualified in the relevant field.

Complex Question

A single question that contains two hidden questions, forcing an unwarranted admission.

Argument ad Hominem

Attacking the person rather than addressing the argument.

Accident

Wrongly applying a general rule to a specific case that is an exception to the rule.

Converse Accident

Drawing a broad generalization from an exceptional or limited case.

False Cause (Post Hoc)

Assuming a causal connection exists simply because one event follows another.

Petitio Principii (Begging the Question)

Using circular reasoning in which the conclusion is assumed in the premises.

Argument ad Populum (Appeal to the People)

Supporting a claim by exploiting emotions, snob appeal, or bandwagon popularity.

Argument ad Misericordiam (Appeal to Pity)

Using pity or guilt rather than evidence to persuade.

Argument ad Baculum (Appeal to Force)

Using threats or force to secure acceptance of a conclusion.

Ignoratio Elenchi (Irrelevant Conclusion)

Offering premises that support a conclusion different from the one claimed.

Equivocation

Using a word or phrase in multiple senses within the same argument, causing ambiguity.

Amphiboly

Grammatical ambiguity that allows multiple interpretations of a statement.

Composition

Assuming the whole has a property because its parts have that property.

Division

Assuming parts have a property because the whole possesses that property.

Red Herring

Diverting attention from the real issue by introducing an unrelated topic.

Straw Man

Misrepresenting or oversimplifying an opponent’s view to refute it more easily.

Weak or False Analogy

Basing an argument on a comparison that is too dissimilar to be persuasive.

Slippery Slope

Claiming without evidence that one event will trigger a chain of disastrous events.

False Dichotomy (Either-Or Fallacy)

Presenting only two alternatives as if they are the only possibilities when more exist.