PHILOS Fallacies

fallacy of relevancy

supporting a conclusion with premises that are not relevant to the truth of the conclusion.

fallacy of relevancy: Ad hominem argument

claims to support a conclusion by attacking the person who asserts the opposite.

fallacy of relevancy: Guilt by association argument

claims to support a conclusion by criticizing the company kept by the person who asserts the opposite.

fallacy of relevancy: Tu quoque argument

claims to support a conclusion by accusing the person who asserts the opposite of hypocrisy or inconsistency.

fallacy of relevancy: Vested interest argument

claims to support a conclusion by alleging that someone who asserts the opposite has an interest in doing so.

fallacy of relevancy: Straw man argument

claims to refute an assertion by attacking a much less plausible position similar to it.

fallacy of relevancy: Arguments by authority [or “appeals to authority”

claims to support a conclusion by citing the opinion of someone without giving good reason to think that this person is reliable.

fallacy of relevancy: Appeals to Ignorance

claims to support the truth of a conclusion by arguing that no one can disprove it.

Semantic Fallacy

argument relies on words or phraseswith ambiguous or vague meanings.

Semantic Fallacy: Sorites arguments

claims to show that something is an instance of a vague predicate by arguing incrementally from a clear case.

Semantic Fallacy: fallacy of ambiguity

(1) argument uses a phrase with more than one distinct meaning, and (2) the argument seems good only if the phrase is used with one meaning at onepoint in the argument, and with another meaning at another point in the argument.

Deductive fallacy

claims that the truth of her premises would provide absolute support for the truth of the conclusion when in fact the truth of the premises would not.

Deductive fallacy: Circular reasoning [or begging the question]

when one of the premises in her argument assumes the conclusion.

Inductive Fallacy

claims that the truth of her premises would provide a certain degree of support for the truth of the conclusion when infact the truth of the premises would only provide some significantly weaker degree of support.

Inductive Fallacy: Hasty generalization

infers that an entire class of things has some property based only on the fact that some of its members do.

Inductive Fallacy: gambler’s fallacy

thinks that an event in a sequence of independent events, like in a series of coin tosses, is more likely to occur in a certain way because it has not occurred that way recently.

Inductive Fallacy: False cause [post hoc ergo propter hoc]

concludes that A causes B only because A happens before B, or only because A and B happen at the same time.

Inductive Fallacy: conjunctive fallacy

believes that the conjunction, or combination, of two attributes or events (A and B) is more likely to occur than one of its parts (A).

Inductive Fallacy: Base rate fallacy

ignores the base rate of an attribute or event when inferring the likelihood of that attribute or event in a specific case given some evidence.

Deductive fallacy: Affirming the consequent

If A, then B.

B is true.

Cannon ball A is true.

Deductive fallacy: Denying the antecedent

If A, then B.

A is false.

Cannon ball B is false.