A Relationship between an Plan and a Assumption whereby the Plan is based on the Assumption (i.e. used during Planning) and may be invalid if the Assumption fails to hold An Assumption in a Plan-Assumption relationship is also the Assumption in a Planning-Assumption Relationship for the Planning Activity that produced the Plan
(=> (Plan-Assumption ?Plan ?Assumption) (Exists (?Planning) (And (Planning ?Planning) (Actual-Output ?Planning ?Plan) (Planning-Assumption ?Planning ?Assumption))))