Semantic Web - slide "Theoretical Foundations"

First Order Logic (First Order Predicate Calculus) is the basis for most Knowledge Representation
- an arbitrary example
DAML+OIL was heavily influenced by work in Description Logics, a subset of First Order Logic limited to constructs with tractable (polynomial time) complexity for key algorithms
- see http://dl.kr.org for additional information on Description Logics
- Ian Horrocks provided a good overview at a recent workshop
if you don't find a given feature in DAML+OIL, it's likely because it can't be supported in DL
the semantics of DAML+OIL (and later RDF and OWL) have been expressed in 2 forms:
- model theoretic: mathematical set-theoretic formalism
- axiomatic: machine-readable KIF representation
the formal semantics are expected to result in better specifications and implementations