“…These range from excplicitly encoding frame axioms in first-order logic and using theorem proving in order to plan [Green, 1969, Kowalski, 1979, to embedding frame axioms procedurally, or within some aspect of the representation (Fikes and Nilsson, 1971, Hewitt, 1972, Pednault, 1985, to monotonic approaches that use either domain-dependent "explanation closure axioms" [Haas, 1987, Schubert, 1989, Weber, 1989, that attempt to enumerate the complete set of actions which can alter the truth value of a proposition, or equivalently that use complete sets of independence assertions [Hayes, 1971, Georgeff, 19871, to (most popularly), the definition, development, and use of non-monotonic logics [Reiter, 1980, McCarthy, 1977, Lifschitz, 1987, Haugh, 1987, Shoham, 1986, Kautz, 1986] that use unsound inferences to conclude that things do not change unless there is explicit knowledge to the contrary.…”