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Re: Storing data and code in a Db with LISP-like interface

From: Nick Malik [Microsoft] <nickmalik_at_hotmail.nospam.com>
Date: Fri, 28 Apr 2006 09:23:34 -0700
Message-ID: <p8ydnSNwfeLq3c_ZRVn-rA@comcast.com>


"Neo" <neo55592_at_hotmail.com> wrote in message news:1145746437.660905.240120_at_g10g2000cwb.googlegroups.com...

>
> Ok, I see. Suppose we start with the following:
>
> subtype(doctor, human).
> subtype(engineer, human).
> named_instance(john, doctor).
> named_instance(mary, doctor).
>
> And now comes along an alien named bob, who has all the major
> characteristics of a doctor, but he is not a human. How do I handle
> this situation?
>

If this is true, then an alien can be a doctor and Bob can be an alien. Therefore, we can no longer say, for certain, that 'just because john is a doctor, therefore he is human,' because there are now alien doctors. The ruleset change is small.

subtype(doctor, alien).
subtype(doctor, human).
subtype(engineer, human).
named_instance(john, doctor).

named_instance(mary, doctor).
named_instance(bob, doctor).
-- 
--- Nick Malik [Microsoft]
    MCSD, CFPS, Certified Scrummaster
    http://blogs.msdn.com/nickmalik

Disclaimer: Opinions expressed in this forum are my own, and not 
representative of my employer.
   I do not answer questions on behalf of my employer.  I'm just a 
programmer helping programmers.
-- 
Received on Fri Apr 28 2006 - 11:23:34 CDT

Original text of this message

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