DRS: A Set of Conventions for Representing Logical Languages in RDF

RDF, and notations based on it such as OWL, are not very good at representing arbitrary propositions, which are necessary for many applications, including the representation of processes and plans. There are various official (“OWL rules”) and semiofficial (“RuleML”) efforts to solve this problem. DRS is similar in spirit to the OWL Rules system, but different in detail. (For further remarks, see section 3, below.) The key idea behind DRS is to describe a formula as an object. You can think of this as an alternative to reification, or as reification done right, depending on one’s understanding of the slippery term “reification.” An RDF processor must then take such a description as an assertion that the rule is true, if it occurs in an appropriate context. For example, in OWL-S, an appropriate context would be the precondition or effect of a step in a process. The building blocks of a formula are descriptions, terms and atomic formulas. An atomic formula is represented in the XML serialization of RDF thus: