Re: Mixing OO and DB

From: Dmitry A. Kazakov <mailbox_at_dmitry-kazakov.de>
Date: Sat, 23 Feb 2008 11:41:53 +0100
Message-ID: <192zzjjuk0p0a.l8sykjnlixzi$.dlg_at_40tude.net>


On Fri, 22 Feb 2008 15:39:06 -0800 (PST), Marshall wrote:

> On Feb 22, 2:34 pm, "Dmitry A. Kazakov" <mail..._at_dmitry-kazakov.de>
> wrote:

>> On Fri, 22 Feb 2008 13:26:14 -0800 (PST), Marshall wrote: >>> On Feb 22, 12:47 pm, "Dmitry A. Kazakov" <mail..._at_dmitry-kazakov.de>

>>>>> It appears you are somehow claiming that multiplication
>>>>> is not defined on computable numbers.
>>
>>>> Sure. Multiplication (addition, subtraction, division) is incomputable and
>>>> thus cannot be defined.
>>
>>> The claim "multiplication is uncomputable" is amusing.
>>
>> Really? Show me a DFA model of multiplication in R. Let's laugh together.

>
> Oh, so there are additional hidden qualifiers

Come on, don't you have a computer at work? These are comp.xxx groups!

> to your unqualified
> claim that multiplication is uncomputable? You mean specifically
> multiplication on the reals, despite the fact that you were
> responding to a statement of mine that was specifically
> about only the computable reals?

No, that does not save you. You cannot provide any non-trivial finite subset of reals closed on multiplication.

Ah, especially for you (:-)):

_def_ non-trivial subset:

   contains 2  

_def_ closed on multiplication:

   forall x,y in S, exists z in S, such that z = x*y

>> Nobody ever claimed that a circle is not an ellipse.

>
> No one except you:
>
> On Feb 15, 3:13 am, "Dmitry A. Kazakov" <mail..._at_dmitry-kazakov.de>
> wrote:
>
>> Circle value is not an ellipse value. These have different types.

Sure.

> It was my entree into the thread, to chastise you for making broad
> unqualified statements such as that one.

It seems that you do not understand difference between a model and the thing being modeled.

Circle value /= circle
Ellipse value /= ellipse
Circle value /= Ellipse value

"Value" in this context is a CS term. So "circle value" is. That reads: "a value that serves a model for some circle."

Because, obviously, CS /= Geometry (would you challenge this too?), while "circle" is a term of the latter (objections?), therefore, you cannot claim them same. It is a logical fallacy.

>>> "Circle values" is synonymous with "circles"
>>
>> [...]
>>
>> Who said that?

>
> Me. The guy you are talking to, remember? The local
> context? I've challenged the use of the term "circle
> value" to mean something distinct from "circle" several times
> now with you.

You didn't provide any proofs in order to substantiate your claim. Mere repeating "I said so" does not make any point. I already wrote about how an equivalence of the model might be shown in a standard and accepted in mathematics way. You ignored it. I can't help this.

>> It is up to you to prove that this model is adequate to claim them being
>> same. I gave you enough hints that you would not be able provide such a
>> proof. If you still want to square the circle, go on.

This stands, of course.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de
Received on Sat Feb 23 2008 - 11:41:53 CET

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