COMMENT ⊗   VALID 00002 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002	moving[e82,jmc] Common sense axioms for moving objects
C00005 ENDMK
C⊗;
moving[e82,jmc] Common sense axioms for moving objects

	These axioms represent a first attempt at creating a general
purpose common sense data base for giving the conditions and effects of
moving an object from one location to another.  By "general purpose" is
meant that the axioms must be sufficiently general that any intelligent
program that plans to move object could use these axioms without ad hoc
changes, even though additions to deal with genuinely special phenomena
might be required.  The additions may lead to changed conclusion via
circumscription.

	We have objects and places.

	holds(proposition, situation)

	At(object, place) ε propositions

	Top(object) ε places

	Move(object, place) ε actions

	Does(person, action) ε events

	result(event, situation) ε situations

	Attached(object, object) ε propositions

	Clear(ojbect) ε propositions

	Succeeds(person, action) ε propositions

	UNLIKELY(proposition)

	∀p obj place s.holds(Succeeds(p, Move(obj, place)), s) ⊃
holds(At(obj, place), result(Does(p, Move(obj, place)), s))

	It is likely that an object after an event is in the same place
that it was before.

	∀obj pl s p.at(obj,pl,s) ⊃ LIKELY
At(obj,pl,result(Does(p,Move(obj,pl)),s)

	∀obj pl s p.LIKELY(At(obj,pl,s) implies
At(obj,pl,result(Does(p,Move(obj,pl)),s))