Re: Testing for the equivalence relation

"VC" <boston103_at_hotmail.com> wrote in message news:zsednaY9ZNPML1bfRVn-gA_at_comcast.com...
>
> "Dan Guntermann" <guntermann_at_verizon.net> wrote in message
> news:ddKye.14750$H64.14153_at_trnddc07...
>>
>> "VC" <boston103_at_hotmail.com> wrote in message
>> news:BMOdnU1pf_-jyVbfRVn-iQ_at_comcast.com...
>>>
>>> "Dan" <guntermann_at_verizon.net> wrote in message
>>> news:1120613312.060553.18100_at_g14g2000cwa.googlegroups.com...
>>> [...]
>>>> Let me ask this:
>>>> For a question concerning sets A, B, C, if I were to ask whether A = B
>>>> = C, could you tell me how many sets I am talking about? If so, how?
>>>
>>> Of course not. It depends on whether the equality holds between A and B
>>> or/and C. Assuming, A=C & A=B, there is one set only (by axiom of
>>> extensionality).
>>
>> And if I were to give you definitions of all three sets and then ask how
>> many sets are being evaluated to make the determination of whether A=C &
>> A=B by axiom of extensionality, what would your answer be?
>
> The same of course: "I do not know".

I don't know why you say this unless you are trying to be difficult. We must evaluate three operands that are values distinguished from one another.

This distinction is fundamental to the notion of relationship by association in associative data models -- sloppiness and informality notwithstanding.

• Dan