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

From: Pascal Bourguignon <pjb_at_informatimago.com>
Date: Sun, 23 Apr 2006 01:55:15 +0200
Message-ID: <87psj9xj18.fsf@thalassa.informatimago.com>


"Neo" <neo55592_at_hotmail.com> writes:

>>> Now, suppose I wanted to classify an actual tomato as both a fruit and a vegetable, where would I add it to the above "class hierarchy"? (You don't need to show me actual Prolog, just adjust above tree).
> .
>> Prolog is a graph, not a tree.
>> To illustrate it as a tree misses the point.
>> Humans <categorize> in trees, but our brains <think> in graphs.
>
> Yes, I think displaying graphs in tree might mislead some people into
> believing the underlying capabilities are limited to trees; and
> sometimes it is better to display it as a list of statements as Prolog
> does.
>
>> To solve the problem posed, I placed the entire prolog program below, with
> the two facts you provided (Tomato is both a fruit and a vegetable).
>
>> named_instance(john,person).
>> named_instance(mary,person).
>> subtype(apple,fruit).
>> subtype(banana,fruit).
>> subtype(tomato, fruit).
>> subtype(tomato, vegetable).
>
> 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?

By not being dumb, and by modelizing correctly the universe!

doctor is a role, not a human being.

-- 
__Pascal Bourguignon__                     http://www.informatimago.com/
I need a new toy.
Tail of black dog keeps good time.
Pounce! Good dog! Good dog!
Received on Sat Apr 22 2006 - 18:55:15 CDT

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