VAL@SAIL.STANFORD.EDU (Vladimir Lifschitz) (10/25/86)
RAMIFICATION AND QUALIFICATION IN THE BLOCKS WORLD Matt Ginsberg David Smith Thursday, October 30, 4pm MJH 252 In this talk, we discuss the need to infer properties of actions from general domain information. Specifically, we discuss the need to deduce the indirect consequences of actions (the ramification problem), and the need to determine inferentially under what circumstances a particular action will be blocked because its successful execution would involve the violation of a domain constraint (the qualification problem). We present a formal description of action that addresses these problems by considering a single model of the domain, and updating it to reflect the successful execution of actions. The bulk of the talk will involve the investigation of simple blocks world problems that existing formalisms have difficulty dealing with, including the Hanks-McDermott problem, and two new problems that we describe as "the dumbbell and the pulley".