Re: compound propositions
Date: Thu, 18 Mar 2010 19:39:23 -0300
Message-ID: <4ba2ab27$0$12425$9a566e8b_at_news.aliant.net>
> Bob Badour wrote:
> ...
>
>> I, too, find your use of the word sloppy, because a relation is a set >> of things that satisfy a predicate. The relation, itself, doesn't >> satisfy the predicate. Extent or extension is well-defined as a set of >> instances and describes what a relation is: a set of instances that >> satisfy a predicate. >> ...
>
> Maybe, if it is possible to talk theory without ever talking
> implementation (which has its own conceptual, logical and physical
> 'levels'). Personally, if a relation has a header and the header
> satisfies a predicate,
Now you are using "satisfy" to mean something entirely different yet again.
> I have no problem with the statement that a
> relation satisfies a predicate, in the same way that if ISO/IEC
> publishes an IEC definition, I have no problem saying that ISO published
> it.
Neither headers nor relations satisfy predicates. A relation is the extent of some predicate. The tuples of a relation are the instances that satisfy the predicate. The header is a notational artefact of the formalism.
> I believe it is possible to "think outside of the box" without
> completely understanding or agreeing about the box as long as any
> resulting chaos is isolated to just a few people, although I have met
> people who don't think so (and some of them could never agree on the box
> in a hundred years). Exploration is often imprecise (not claiming to be
> much of an explorer myself nor that my musings have any importance
> except to a handful of fanatics here).
> If it's of any help, I'll try to use single quotes more than I already
> do to help show when I suspect my usage is colloquial or might apply in
> to some context other than the one at hand.
Changing the symbol does not obviate the need to define it.
> I think I've exhausted my comments on vocabulary for today.
Received on Thu Mar 18 2010 - 23:39:23 CET