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Re: A

From: Paul <paul_at_test.com>
Date: Sun, 10 Jul 2005 12:08:32 +0100
Message-ID: <42d101b1$0$2907$ed2e19e4@ptn-nntp-reader04.plus.net>


Jan Hidders wrote:

>>> In some sense you might say that is is "too large" to be a set. The
>>> collection of all relations has the same problem. 
>>
>> I'm skeptical to this, but if it is too difficult to explain (or to
>> give an example of a problem), I'll let it be for the moment.

>
> I'll give another hint. Since unary relations are similar to sets you
> can get Cantor's paradox.

Doesn't this only apply if you are considering the set of all relations over all domains? What if you restrict yourself to a finite set of domains? I can't see how Cantor's Paradox would apply in this case.

So rather than having a domain of "the set of all relations", which can't exist, you could have a domain of "the set of all relations over a specified finite set of domains". Or even an infinite set of domains, I suppose, providing it's still a well-defined set.

So the "size explosion" problem here is with the domains rather than the relations?

Paul. Received on Sun Jul 10 2005 - 06:08:32 CDT

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