🚀 go-pugleaf

In article <1992Nov16.091653.1@woods.ulowell.edu> cotera@woods.ulowell.edu writes:

   Can anyone explain why we use logic? Unfortunately, any logical arguments to
   support logic, are unfortunately, invalid.
   --Ray Cote

On the contrary, logical arguments may be not only valid, but also informative.

For instance, to explain why we use classical first order logic (for many
important purposes), logical theorems such as soundness and completeness are
very relevant.  So are fancier theorems such as the non-enumerability of
consequence in 2nd order logic, or Lindstrom's theorem.  

Of course it depends what the argument is intended to accomplish.  A truly
illogical person (perhaps a child) must be trained, not convinced.  A logical
person who wants to gain insight into what he's doing and why can learn a lot
from mathematical logic.  

I believe that this point is originally due to Michael Dummett, "Justification
of Deduction", in _Truth_and_Other_Enigmas_.

	Josh