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Re: The stupidest design I ever saw

From: dawn <dawnwolthuis_at_gmail.com>
Date: 10 Apr 2006 20:31:21 -0700
Message-ID: <1144726281.692452.15690@z34g2000cwc.googlegroups.com>

Neo wrote:
> > > First there is no systematic method that allows one to create the
> > > hierarchy (fig 2) on the basis of the table (fig1) (even after ignoring
> > > the top most and bottom most nodes which represent Universal and NULL
> > > respectively). If you know what that method is, please state it so that
> > > anyone can verify it.
> >
> > 1. Identify all the cylindric sets
> > 2. Connect nodes with the partial order relation
>
> I challenge anyone to follow the above steps and create the shown
> hierarchy from the table, where the names of objects and classes are
> simply identified by different letters (to prevent a user from
> introducing knowledge not encoded in the table).

Perhaps you could award $1000 to anyone who meets your challenge -- as I recall that would not cost you anything, Neo. ;-)

>
> > > Please state THE
> > > square/cell to uncheck which unclassifies cartoon as a mammal
> > > without also unclassifying Garfield and Snoopy as cartoons?
> > >
> > > ______ cartoon real dog cat mammal
> > > Garfield __X___ ___ ___ _X_ __X____
> > > Snoopy __X___ ___ _X__ ___ __X____
> >
> > This is not big deal.
>
> And yet, your response didn't indicate which cell to uncheck to
> unclassify cartoon as a mammal as you alluded earlier.
>
> > Any classification system has to obey transitivity rule:
> > if class A is a subclass of B and if B is subclass C
> > then A has to be a subclass of C.
>
> While classification is transitive in many cases, it is not transitive
> in all cases. Consider the following class hierarchy:
>
> human
> __engineer
> ____bob
> __doctor
> ____sue
>
> Now a friendly alien from Mars (named bill) arrives on Earth. He is
> capable of using his tools to dignose health problems and write
> prescriptions to cure various ailments. This alien is a doctor but he
> is not a human.

Then we need to redefine our terms. If we had said that doctor is-a human, then we cannot say this alien is a doctor until we redefine that is-a relationship. --dawn Received on Mon Apr 10 2006 - 22:31:21 CDT

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