PHIL 250: Introduction to Symbolic Logic

tennant.9@osu.edu

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ELIMINATION RULE FOR IMPLICATION (→E)

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A

A→B

_____________________

B

Explanation in words: In order to infer from a conditional premiss A→B, one must prove the minor premiss A. By taking the indicated step of implication elimination, one thereby rests the resulting conclusion B on the combined assumptions on which the minor premiss A and major premiss A→B respectively rest.

Compare the corresponding introduction rule for →

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[¬I] [∧I] [∨I] [→I] [∀I] [∃I]
[¬E] [∧E] [∨E] [→E] [∀E] [∃E]
[EFQ]
[LEM] [Dil] [CR] [DNE]

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