Why I Like Teaching Logic

Yes, that's what I thought when the comic came up in my feedreader too.Just yesterday I was sketching normalisation for natural deduction for intuitionistic logic, for my advanced undergraduate class and it struck me how <>beautiful<> (and timelessly necessarily true, of course) it all was...

So... how do you feel about the law of the excluded middle? Axiom of choice? What <>is<> a proof? Tarski's definition of truth requires infinite regress: discuss...

OOooh... how about: what logic do you use when you prove that FOL is sound and complete?

I'm not sure how Richard feels about these things, but I like the way that when you teach philosophical logic, you're both proving mathematical results, and engaging in historical and philosophical argle-bargle about it.So, the philosophical questions concerning LEM, Choice, the identity of proofs, etc... are all very interesting philosophical questions, which are illuminated by (but, of course, not <>settled<> by) metamathematical theorems. My views on the philosophy of logic and mathematics aren't so revisionary or radical that they make me question the status of mathematical proofs, such as the soundness and completeness of an axiomatisation of FOL for the standard Tarskian model theory.Oh, and I'd distinguish <>necessity<> from <>certainty<>. Something might be necessary (that, say, (forall p)(p v ~p)) without it being universally agreed that it is...