Re: Mixing OO and DB

From: Marshall <marshall.spight_at_gmail.com>
Date: Fri, 22 Feb 2008 15:39:06 -0800 (PST)
Message-ID: <dca5ccbf-86e6-47de-9aac-3ea85da6a63f_at_e6g2000prf.googlegroups.com>


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>
>
> >>>> Of course they do. For example this vanishes:
>
> >>>> forall x, circle exist y, circle twice as big
>
> >>> Does this mean that you are claiming that given a
> >>> computable specification of a circle, it is impossible
> >>> to determine a computable specification of a
> >>> circle with twice the radius? Or maybe area?
>
> >> No, you claimed that a set of computable circles retain the properties of
> >> the set of all circles. This is wrong, as my example shows.
>
> > You example is sufficiently fuzzily worded that it cannot
> > be said to show anything.
>
> No, it is worded precisely enough to show that properties are not preserved
> by the model. Do you object that?

Yes. I object to the idea that your example has anything even vaguely like precision associated with it. Does "twice as big" refer to the radius or the area? Does "properties are not preserved" mean *all* properties are not preserved, or *some* properties are not preserved? But I already asked what your intent was and you declined to specify, twice now. Whatever may be the reason for your failure to respond, it leaves me with no possibility of determining what meaning you intended it to have.

Meaningless statements cannot be said to show anything.

> [... irrelevant and obvious stuff about geometrical subsets ...]
>
> >>> 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 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?

Perhaps if you learn to recognize when you are doing that, or if you learn how to answer clarifying questions when asked, it will make it possible for you to engage in productive conversation.

On the other hand, the conversation went exactly like this:

Me: It appears you are somehow claiming that multiplication is not defined on computable numbers.

You: Sure. Multiplication ... is incomputable ...

Me: [ha ha]

You: Really? Show me ... multiplication in R.

Can you give me any reason to believe that your bait-and-switch above, from my very explicit qualification of computable reals, to your revising your statement to be about the full set of reals instead, is an honest mistake?

> 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.

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

> > "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. Since my challenges were left unanswered they remain in force. So for example *in this thread* when you say:

> Again, circle value is a model for circle. Period.

It means no more and no less than "a circle is a circle" a statement with which I have nothing but agreement.

I will say, for the umpteenth time, that if you want to supply a specific definition for the purposes of this discussion you are free to do so, but until you do, mine win, since they are the only ones present.

> 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.

You gave vaguely worded unqualified broad claims that were obviously false in at least some contexts and specifically false in the
context I supplied. You provided no context or definitions yourself despite repeated requests to do so.

> >> So far your single argument was that you could
> >> find a circle for each circle value.
>
> > That would not be my argument since I do not recognize
> > the term "circle value" as being distinct from "circle."
> > If you wish to supply a specific definition for this or
> > some other term, please do so. However, merely
> > saying something "as defined in geometry" does not
> > qualify.
>
> Geometry is a commonly accepted mathematical discipline
>
> http://en.wikipedia.org/wiki/Geometry
>
> which part, called "Euclidean" defines the term circle.
>
> http://en.wikipedia.org/wiki/Circle
>
> As such a reference to it certainly qualifies as a definition of circle.

Apparently you are unaware of what a definition is.

A definition is a statement that introduces a term, either previously undefined or explicitly to be redefined, and provides it with a meaning in terms of a combination of previously defined terms or undefined primitives. Definitions always exist within a specific context.

Clearly a handwavey gesture in the direction of "a commonly accepted mathematical discipline" or a wikipedia page is not a definition. The reference to wikipedia pages that don't even mention the terms in question (such as "circle value") is especially weak.

Marshall Received on Sat Feb 23 2008 - 00:39:06 CET

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