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Re: Counting propositions

From: Alan <alan_at_erols.com>
Date: Thu, 17 Jun 2004 16:22:19 -0400
Message-ID: <2jecrrF10qrcbU1@uni-berlin.de>


Now _there's_ great example of bottom posting...

"Tony" <andrewst_at_onetel.net.uk> wrote in message news:c0e3f26e.0406171213.73e101f7_at_posting.google.com... > "x" <x-false_at_yahoo.com> wrote in message news:<40d1ac45_at_post.usenet.com>...
> > **** Post for FREE via your newsreader at post.usenet.com ****
> >
> >
> > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > news:c0e3f26e.0406170609.39c1b7bd_at_posting.google.com...
> > > "x" <x-false_at_yahoo.com> wrote in message
> > news:<40d16fd6_at_post.usenet.com>...
> > > > **** Post for FREE via your newsreader at post.usenet.com ****
> > > >
> > > >
> > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > news:c0e3f26e.0406170106.2e3f34ac_at_posting.google.com...
> > > > > "x" <x-false_at_yahoo.com> wrote in message
> > news:<40d02f27_at_post.usenet.com>...
> > > > > > **** Post for FREE via your newsreader at post.usenet.com ****
> > > > > >
> > > > > >
> > > > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > > > news:c0e3f26e.0406160241.31623d1c_at_posting.google.com...
> > > > > > > "x" <x-false_at_yahoo.com> wrote in message
> > news:<40cf02c7$1_at_post.usenet.com>...
> > > > > > > > **** Post for FREE via your newsreader at post.usenet.com



> > > > > > > >
> > > > > > > >
> > > > > > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > > > > > news:c0e3f26e.0406150554.6822ed6f_at_posting.google.com...
> > > > > > > > > "x" <x-false_at_yahoo.com> wrote in message
> > news:<40cecf85_at_post.usenet.com>...
> > > > > > > > > > **** Post for FREE via your newsreader at
post.usenet.com
> > ****
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > "Tony" <andrewst_at_onetel.net.uk> wrote in message
> > > > > > > > > > news:c0e3f26e.0406150222.fe2eea5_at_posting.google.com...
> > > > > > > > > > > "x" <x-false_at_yahoo.com> wrote in message
> > news:<40ce9db7_at_post.usenet.com>...
> > > > > > > > > > > > Ok. But why there is a need to know this number ?
> > > > > > > > > > > > It is like saying "today I made 100 affirmations".
> > > > > > > > > > >
> > > > > > > > > > > Have you never wanted to know how many of something
you
> > had?
> > > > Can
> > > > you
> > > > > > > > > > > not envisage a large business wanting to know, for
> > example,
> > > > how
> > > > many
> > > > > > > > > > > employees it has?
> > > > > > > > > >
> > > > > > > > > > Employees yes. Propositions no.
> > > > > > > > >
> > > > > > > > > Very droll ;-)
> > > > > > > > >
> > > > > > > > > But the fact is that from the N propositions we have that
say
> > "We
> > have
> > > > > > > > > an employee named xxx with salary yyy ...", we can deduce
the
> > useful
> > > > > > > > > fact that we have N employees - simply by counting the
> > propositions.
> > > > > > > >
> > > > > > > > What made you so sure.
> > > > > > >
> > > > > > > What makes you so unsure? Are you making some kind of
> > philosophical
> > > > > > > point that I'm not getting?
> > > > > >
> > > > > > Well, because you don't directly count employees, but you count
> > propositions
> > > > > > about employees instead, it is a legitimate question to ask if
the
> > result is
> > > > > > accurate and why.
> > > > > >
> > > > > > Other reasons:
> > > > > > - the database may contain propositions about past, current and
> > future
> > > > > > employees
> > > > > > - the database may contain propositions about employees in
different
> > > > > > relations (or relvars)
> > > > > > - it might be hard to distinguish propositions about employees
from
> > other
> > > > > > propositons in the database
> > > > >
> > > > > Well, you ceertainly have to know what the propositions mean
before
> > > > > you can get a meaningful answer by counting them. If the
propositions
> > > > > include past and future employees then you should ensure that you
only
> > > > > count the propositions about current employees by adding the
> > > > > appropriate WHERE clause.
> > > > >
> > > > > It shouldn't be at all hard to distinguish propositions about
> > > > > employess from other propositions in the database, because a
> > > > > relation/table must only hold propositions of one type.
> > > >
> > > > So you say that the employees are in *one-to-one correspondence*
with
> > the
> > > > propositions about employees, or something like that and this is the
> > reason
> > > > you can count propositions to determine the number of employees ?
> >
> > > I do, though I sense I may be walking into a trap ...
> >
> > :-)
> >
> > > I guess the term "external predicate" comes in here, i.e. the
> > > knowledge that these propositions EACH ??? assert the employment of 1
> > > employee is implicit.
> >
> > You see, there are propositions that assert the employment and
propositions
> > that assert other things about the employee.
>
> Yes - like a table of employee_salary_history may assert 7 facts about
> 1 employee.  But I know that, because an employee is identified by
> Emp_id (or whatever), and this table of propositions is not.
>

> > > From that, one can deduce that the existence of
> > > N propositions implies the existence of N employees.
> >
> > Not true. There might be more propositions per employee (without
> > duplicates).
>
> Not in the table of propositions that has Emp_ID as the key there
> can't be.
>

> > Why do you insist in counting the propositions, for counting the
employees
> > then ?

>
> Because it works? ;-) Received on Thu Jun 17 2004 - 15:22:19 CDT

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