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How can I find which lemmas are used by the simp, auto methods, etc?
In one concrete case, I have a goal like:
lemma "x ∉ dom S ⟹ Something"
apply auto
and after applying auto I get: ¬ Something ⟹ ∃y. S x = Some y. I would like to find out why the whole goal is reversed like this, so that I can delete the respective rules from the rewriting.
I already tried using [[simp_trace_new mode=full]] apply auto and using [[simp_trace]] apply auto, but did not find information about what exactly caused auto to do this transformation.