Logic / Unit 5 Logic 193 short lesson, about 20 seconds
Modus Ponens as a Proof Move
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The idea
From lines p ⊃ q and p, derive q.
In practice
1. A ⊃ B. 2. A. 3. B (1, 2, MP).
Where people slip
The rule needs the whole line to be the conditional. A conditional buried inside a larger formula is out of reach.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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