Disjunctive Syllogism 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 p ∨ q and ~p, derive q.
Show
1. A ∨ B. 2. ~A. 3. B (1, 2, DS).
Watch for
Deny a disjunct to release the other. Affirming a disjunct releases nothing (155) — the proof system won't even let you write it.
Builds on
Unlocks
- Nothing yet depends on this.