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logic

Proving invalidity by swapping in new content

taught

Keep the argument's pattern, swap the content, and get obviously true premises with an obviously false conclusion.

Taught in

Proving invalidity with counterexamples
Introduction to Logic

Requires

judge-validity-informally required

Required by

Checking whether a proposed counterexample works required
Validity depends only on form required

Local knowledge map

Local knowledge map

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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.