Re: Asserting subclasses of open ranges or domains

On 2009-09-09, Pat Hayes wrote:

> The DC comment you appeal to is an indicator that, as you say, the 
> "actual" range is not universal, but its extent has not yet been 
> formalized.

Yes. If we then wish to deal with something like that, we're also 
importing a whole new set of problems. As an example, the post you're 
replying to seems to be operating not in the usual bivalent logic, but 
in a modal one, complete with necessities and possibilities that are 
several from from truths, falsities, or even unknowns.

> But asserting subsets of it - adding sufficient conditions - does not 
> help any towards formalizing the actual range, even partially. The 
> only thing that will do that is to somehow restrict the range with 
> necessary conditions.

I'd argue that given the existence of modal logic, you could probably 
formalize these sorts of ideas, and even calculate with them. But the 
result would be even more unwieldy than what we have now, so quite 
certainly they shouldn't be embedded into any SW standard, at least 
before some real life experience has been gained with bivalent (or given 
unknowns and the open world assumption, ternary) logic.
-- 
Sampo Syreeni, aka decoy - decoy@iki.fi, http://decoy.iki.fi/front
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Received on Wednesday, 9 September 2009 16:01:30 UTC