[FOM] Re: Arithmetic-free theory of formal systems?

[Matthew Frank]

Tim Chow has been asking for a theory of formal systems, where the theory
can be described without words like "finite set".  With that constraint,
my reference to Jeroslow (JSL 38 (1973), 359-367) won't help; I don't
know if anything will.  Still, the paper is short, it takes a rather
non-arithmetical approach, and it gets a nice result; I recommend it.
--Matt