Previous Next

Canonical Forms

Consider the expression:

Man which hasSex male.

This is a well formed and sensible expression: a Man is a (kind of) Person, and can thus be related to a SexValueType via hasSex. In addition, there is no cardinality problem as we’re not asserting that a Person has two different sexes. However, we can see that the criterion hasSex male is redundant as we already know that about a Man because hasSex male is part of the definition of the category Man.

The terminology engine is able to reason in this way as well, and reduces categories to a canonical form. This consists of a basic category and a collection of criteria with any unnecessary criteria like those above removed.

Try browsing the expression:

Man which hasSex male.

You will see that the browser opens simply on the category, Man.

Previous Next
Making the impossible very difficult, ©OpenGALEN.org, All rights reserved