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logic

Modus ponens

taught

If P then Q; P; so Q.

Taught in

Requires

Required by

Local knowledge map

Local knowledge map

"If" versus "only if" Denying the antecedent Derived rules: MT, DS, DNE, and De Morgan Destructive dilemma Drawing the conclusion a conditional allows Hypothetical syllogism and the dilemmas as derived rules Recognizing named forms in everyday arguments Telling the valid conditional forms from their look-alikes The biconditional connective Affirming the consequent Constructive dilemma Hypothetical syllogism Modus tollens The conditional connective: antecedent and consequent Modus ponens Addition Conjunction (the argument form) Disjunctive syllogism Sentence letters and a symbolization key Simplification The four categorical statement types (A, E, I, O) Why logic uses symbols Validity depends only on form Proving invalidity by swapping in new content Recognizing substitution instances of a form

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Solid arrows are required prerequisites; dashed are recommended or helpful. Lower rows are more foundational. Click any box to jump to that concept.