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How to change the order of premises in a rule? For instance, in Isabelle's natural deduction rule:

mp: ?P ⟶ ?Q ⟹ ?P ⟹ ?Q

Can we change the order to:

?P ⟹ ?P ⟶ ?Q ⟹ ?Q

I can use rev_mp or define a new lemma, but what I am looking for is whether there is a theorem modifier that changes the order of premises.

user703016
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Fadoua
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1 Answers1

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The premises of a theorem can be rotated with the attribute rotated. You can also specify the number of premises to rotate, e.g., mp[rotated 1]. AFAIK there's no attribute for arbitrarily permuting the premises.

Andreas Lochbihler
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