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

>> Suppose we start with:
>> 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.

Now I am really dumbfounded. What is the definition of a class vs subType vs a role? And what exact steps can I take to determine which type of thing it is? What general questions can I ask, what general answers should I expect in order to determine if a thing is a class, subType or role? (my dictionary say a doctor is a person and nothing about a role).

Also if doctor is a role, would there be a statement such as: named_instance(doctor, role).

And what is a role? An atom? Received on Sat Apr 22 2006 - 20:33:41 CDT