venta

I would hazard that the syntactic representation of knowledge is about using precise formal vocabularies to represent stuff and the properties of such stuff (model-theoretic semantics) whilst the semantic representation of knowledge is the abstract system the syntactic representation of knowledge is describing. So maybe RDF model theory is a semantic representation of knowledge with stuff like RDF/XML and N-tripes describing it in formal syntax. (Maybe I'm totally wrong, but if you attach meaning to data it strikes me you have information, and if you (or a machine) can make inferences based on that information, doesn't it then become knowledge?) Luckily the definition of the third term is easy; it's an obvious reference to the funky computer Tom Cruise uses in Minority Report.