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Re: What predicates the following relation represents

From: mAsterdam <mAsterdam_at_vrijdag.org>
Date: Thu, 01 Apr 2004 20:59:43 +0200
Message-ID: <406c66a0$0$572$e4fe514c@news.xs4all.nl>


Mikito Harakiri wrote:

> "mAsterdam" wrote
  >>I'll (reluctantly) join the speculation a little bit to explain,
>>I will try to conform to the guesswork Eric has done:
>> |--SALE(Nuts, 0)
>>may mean something like: Mr FooBar sold 0 nuts today.
>>|--!exists x>0: SALE(Nuts, x)
>>may mean something like: Mr FooBar did not sell nuts today.
>>
>>Do they convey the same fact? Not by itself. Maybe they do,
>>but we don't have what we need to decide it.
>
> What exactly is missing?

Exactly the meaning of

> SALES
> =====
> PART SOLD
> ---- ---
> nuts  10
> nuts  15

You originally asked:
> Is SALES a legal relation? Is database really a repository of facts?

If you, by "legal" mean "some rows I can put into some table", then the answer to your first question is obviously: sure. However, in order to become statements, they need meaning. The proper (canonical, or 'legal' if you want) way to do that is by formulating a predicate.
Now the database can become a repository of facts.

Reiterating:
Q: What is missing?
A: The predicate.

>>Maybe we could decide if we knew wether mr FooBar tried
>>to sell nuts today.
>>
>>This is not in the information we were provided with, so even more
>>speculation is called for. This does not seem very useful.
>>Most of the guessing would be unnecessay if there would have been
>>something to go on at the start: the predicate.

> 
> How do you expand the example in order to resolve the ambiguity. I prefer
> formal solution, not just vague call for "more semantics".

Your qualification is wrong, and put in an annoying way - but I'll get over the latter.

I asked you to give the specific facts your example is supposed to state. Granted that is a call for semantics. But not just any.
It is a specific call for only the semantics necessary to answer your question.

>>>If you refer me to Model theory, let me think it over.
>>Not that I am aware of. Which model theory?

> I was just playing with the correspondence:
> Syntax -> Logic
> Semantics -> Model Theory

I am so sorry to bore you all if everybody else here knows which model theory you are talking about. I really don't. So, again: which model theory?

>>>>To achieve conceptual integrity one needs concepts.
>>>
>>>Be careful using the same abstract word twice in the sentence.
>>
>>Where is the danger in this one?

>
> Conceptually speaking might jeopardize listener's conceptual integrity.

You prefer confirmation of your beliefs? ;-) Received on Thu Apr 01 2004 - 12:59:43 CST

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