FOM: Wider cultural significance

[Joe Shipman]

Simpson:
>In my opinion, the way to do
>so is to (a) accept the G"odelian conclusion that there is no *purely
>mathematical* secure foundation of mathematics, and (b) seek another,
>better foundation by integrating mathematics with the rest of human
>knowledge.

>One approach to (b) would be to argue that PRA is consistent because
>the physical world provides a model of it, and then to justify at
>least a significant fragment of mathematics by reducing it to PRA, a
>la Hilbert's program of finite reductionism.

What arguments that the physical world provides a model of PRA do not
also apply to PA?