FOM: modeling PRA in the physical world

[Schalekamp, Hendrik J.]

> From:          Stephen G Simpson <simpson at math.psu.edu>
>  > I would say, that potential infinity (our ability to distract from
>  > resource bounds) is peoples *invention*. It does no hold in our
>  > universe in any direct sense. 
 
> You define potential infinity subjectively as `our ability to distract
> from resource bounds'.  This formulation prejudges the issue by
> assuming that potential infinity is a subjective phenomenon.  By
> contrast, Aristotle defined potential infinity objectively, as `that
> which is always becoming other and other'.  For instance, winter is
> potentially infinite, because every winter is followed by another
> winter. 

This example does not seem to hold water, since (according to modern 
astrophysics)  the sun will engulf the earth at some stage and hence 
the won't be any more winters (or water for that matter). Can we 
actually even give a reasonable example of potential infinity? All the 
examples I've tried so far seem to come up against the same problem 
as the winter example.

Regards
Hendrik Schalekamp
University of Cape Town, South Africa

Carnun, Son of Danu
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