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Re: Motion 52: final "Expressions" text for vote



John,

I thought Section 7 required the use of point function domains of definition based on the set of real numbers and/or its two-point compactification.

Permitting a foundation based on the one-point compactification of the reals would be a step in the right direction.

What about a foundation based on both the one- and two-point compactifications as well as other consistent systems.

The point is that it is impossible to list the set of all possible flavors that might provide useful interval systems. So, why is it no better to impose the smallest possible set of constraints on flavors?

Cheers,

Bill


On 11/27/13 3:33 PM, John Pryce wrote:

Bill

On 2013 Nov 25, at 20:18, G. William (Bill) Walster wrote:
On 11/24/13 4:40 PM, Michel Hack wrote:
Bill Walster wrote:
For a system of real, not extended real intervals, the domain
of div(x,y) and recip(x) can be R^2 and R, respectively.  See
Table 9.1 on page 21.
???  The inverse of 0 is not defined in the Reals, so the domains
indeed have the holes described in Table 9.1.

This does not in any way constrain flavours from extending those
domains in a flavour-specific manner for *non-common evaluations*.
It sure does if my universal set of intervals includes the elements of the one-point compactification of the reals, R \cup \infty because 1/0 = \infty.
The intention of the flavors scheme was that an interval model like the one you describe can indeed be a flavor. Please explain just what part of the specification in §7 prevents this.

John