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Modus Ponens as a Proof Move

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

From lines p ⊃ q and p, derive q.

Show

1. A ⊃ B. 2. A. 3. B (1, 2, MP).

Watch for

The rule needs the whole line to be the conditional. A conditional buried inside a larger formula is out of reach.