[FOM] Tolerance Principle

[Harvey Friedman]

On 2/8/06 4:18 AM, "Thomas Forster" <T.Forster at dpmms.cam.ac.uk> wrote:

> 
> 
> 
> I think the two systems have to interpret arithmetic in the same
> way......  (which NF and ZFC do not)
> 
>    tf
> 
> 

The question of whether or not two appropriate systems interpret arithmetic
in the same way has NOTHING to do with the question of whether one of the
systems is interpretable in the other.

E.g., a lot of (weak) set theories are interpretable in a lot of arithmetics
(systems of arithmetic), and vice versa.

Harvey Friedman