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logic

Formal versus informal fallacies

taught

A formal fallacy is a bad form; an informal fallacy is a defect of relevance, evidence, assumption, or language, and can hide in a valid argument.

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Requires

Required by

Local knowledge map

Local knowledge map

Ad hominem Appeal to emotion Appeal to force Appeal to ignorance Appeal to inappropriate authority Appeal to popularity Begging the question (circular reasoning) Equivocation False dilemma Hasty generalization Loaded (complex) question Post hoc (after this, therefore because of this) Red herring Straw man The fallacy of composition The genetic fallacy The four-question fallacy check Formal versus informal fallacies Checking the named forms by truth table Telling a named form from its neighbors Evaluating any argument with three questions Recognizing named forms in everyday arguments Addition Affirming a disjunct Conjunction (the argument form) Destructive dilemma Hypothetical syllogism Judging premises and reasoning separately Simplification Telling the valid conditional forms from their look-alikes What makes an inductive argument cogent

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