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Full Idea
A puzzle about modus ponens is that the major premise is either false or unnecessary: A, If A then B / so B. If the major premise is true, then B follows from A, so the major premise is redundant. So it is false or not needed, and contributes nothing.
Gist of Idea
In modus ponens the 'if-then' premise contributes nothing if the conclusion follows anyway
Source
Stephen Read (Formal and Material Consequence [1994], 'Repres')
Book Ref
'Philosophy of Logic: an anthology', ed/tr. Jacquette,Dale [Blackwell 2002], p.243
A Reaction
Not sure which is the 'major premise' here, but it seems to be saying that the 'if A then B' is redundant. If I say 'it's raining so the grass is wet', it seems pointless to slip in the middle the remark that rain implies wet grass. Good point.
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