Re: Normalisation

From: VC <>
Date: Wed, 13 Jul 2005 17:28:41 -0400
Message-ID: <>

"Jan Hidders" <> wrote in message news:%reBe.144048$

> VC wrote:

>> "Jan Hidders" <> wrote in message
>> news:FwWAe.143403$
>>>VC wrote:
>>>>"Jan Hidders" <> wrote in message
>>>>>Ah, but now you are using the domain or relations, right? There is a
>>>>>problem with that domain. It doesn't exist. The collection of all
>>>>>relations is a proper class, and not a set, but domains have to be
>>>> The collection of all relations is most certainly a set, and
>>>> therefore, a domain, domain being a synonym of set. The term "proper
>>>> class" implies that you talk in terms of set theory other than ZF (
>>>> Zermelo - Fraenkel ) ). There is no need to do so for the reltional
>>>> model unless you can show there is ;)
>>>There is indeed no such need, unless of course you want to define the
>>>domain of relations, which you cannot do in ZF.
>> The onus of proof of such impossibility is squarely on your shoulders.
>> Please oblige (define a collection/domain of relations, within ZF, which
>> ain't a set).
> Defining a collection of relations within ZF that is not a set, is neither 
> here nor there.

I am sorry but your response does not make any sense whatsoever. What is "neither here nor there" supposed to mean ?

Please define a collection of relations obeying ZF axioms and show it's not a set.

> -- Jan Hidders Received on Wed Jul 13 2005 - 23:28:41 CEST

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