That’s not a proof; it’s an (invalid) inference — doubly invalid if you have no form for imperfect induction, but in any case invalid by the introduction of ‘we know that’ as a modal operator (are we doing epistemic logic? p->q |= p->Kq isn’t a valid schema).

It’s not in FOL, because of the modal operator, and it’s an instance of a schema, not a proof. Not what I asked for.

Anyway, I wrote something on Maps of Meaning in case you’re interested.

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Lecturer in Philosophy, University of St. Andrews — personal website: https://axdouglas.com/

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