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Home -> Community -> Usenet -> comp.databases.theory -> Re: Storing data and code in a Db with LISP-like interface
>> 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? Received on Sat Apr 22 2006 - 17:53:57 CDT
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