Abstract
SGLD has been implemented in Prolog, and performance testing shows the efficacy of using semantic information to guide search. As well the features described above, SGLD has facilities for imposing sort value deletion and for embedding equality. Sort value deletion is imposed via the same mechanism as the truth value deletion, but throughout deductions. Equality is embedded via an extension of the RUE and NRF inference rules [Digricoli, 1979].