Higher Order Logic unifies
- Map RDF triple set into existential assertion of conjunction
- Add negation, (implication, mutually disjoint sets,...)
- Define as new property, but need syntax to avoid reification.
- Add quotation and easier syntax for quantification
- Higher order logic is inescapable.
- Abandon completeness (being about to prove all true sentences)
- Require consistency (not of all data, just of languge!)
