Semantic Nets/Inheritence

• You can specify lots of different relationships (arcs).
• Probably the most important is Inheritence. Why? Representational Efficacy.
• Inheritence is the Is-A or subcategorisation arc. A Mammal Is-A animal.
• Inheritence allows default reasoning, but defaults can be explicitly overridden
• An instance-of arc is like inheritence, but it can't be inherited from.
• Kappa uses these relationships when you build your knowledge base (and Java uses inheritence).
• See the semantic nets lecture.