Re: On view updating

From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Sat, 25 Sep 2004 23:49:58 +0200
Message-ID: <4155e806$0$78753$e4fe514c@news.xs4all.nl>

Marshall Spight wrote:

> mAsterdam wrote:

>>I said it a while ago, I'll say it differently now: IMHO only the
>>*defining* operators should participate in any definiton of a type.
>>Other operators do *not* belong there.

>
> First I think I understand this, then I don't, then I do again.

Thank you for showing interest.

> Can you expand on what you mean?

I'll try. First I dig out stuff from an earlier post about this idea. From the thread "It don't mean a thing ...": http://groups.google.nl/groups?hl=nl&lr=&ie=UTF-8&threadm=40c45fd9%240%2436861%24e4fe514c%40news.xs4all.nl&rnum=3&prev=/groups%3Fq%3Dtype%2B%2522makes%2Bsense%2B%2522%2Bgroup:comp.databases.theory%2Bauthor:mAsterdam%26hl%3Dnl%26lr%3D%26ie%3DUTF-8%26scoring%3Dd%26selm%3D40c45fd9%25240%252436861%2524e4fe514c%2540news.xs4all.nl%26rnum%3D3

Maybe that clears it up a little. Some selected (self-)quotes:

 >------------------------------------------------------------

> semantics: meaning
> pragmatics: use
>
> It has to do with layers of communication.
> Some prefer to distinguish only two layers (syntactic & semantic),
> others more (fatic, syntactic, sigmatic, semantic, pragmatic).
...
> successor does, addition - however useful -
> does not affect the meaning of 'natural number'. Yet IOW:
> Addition affects the use of natural numbers, not the meaning.
...
> The only operations I want to exclude as part
> of their definition are the ones not used to
> define them. Makes sense, no?

...
(The distinction meant is the distinction between semantics and pragmatics, for short: meaning and use).
> Now why would I want to make a distinction others do not?
>
> It is because I suspect a lot of the miscommunication
> between people from different schools of thought is
> due to stretching the meaning of school-internal
> words when confronted with problematic issues,
> partly to avoid the use of *their* concepts,
> partly to cover up paradigmatic blind spots.
> Not unlike the not-invented-here syndrome.
>
> Three examples would be
>
> 1. Orthogonal persistence in the object school to
> dissmiss all problems of data sharing as 'implementation issues'.
>
> 2. Stretching *type* in the relational school to dismiss 'class'
> as a valid concept and still have it.
>
> 3. (Most unfortunate:) stretching *meaning* to include *use*.

>------------------------------------------------------------

Neat (disciplined) use of 'type' and 'types' would (I hope) undo some of this cover-up.

> I suspect this definition can only exist in the face
> of encapsulated state;

Sorry, I don't understand - which definition can only exist where?

> otherwise
> there is no distinction between a function that is part of
> the definition of a type and one that isn't.

One difference: a type would be existentially dependent on no other than its defining functions, rendering these functions essential to the type, the others, as add-ons, less fundamental. Received on Sat Sep 25 2004 - 16:49:58 CDT