Constructive Dilemma as a Proof Move
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State
From (p ⊃ q) · (r ⊃ s) and p ∨ r, derive q ∨ s.
Show
The two-conditional package plus the trigger disjunction yields the outcome disjunction.
Watch for
The conditionals must arrive as a single conjoined line. Two loose conditionals need a Conj step first (198).
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- Nothing yet depends on this.