Abstract
In this paper, we present an analysis of planning with uncertain information regarding both the state of the world and the effects of actions using a Strips- or (propositional) Adl-style representation. We provide formal definitions of plans under incomplete information and conditional plans, and describe Plinth, a conditional linear planner based on these definitions. We also clarify the definition of the term “conditional action, ” which has been variously used to denote actions with context-dependent effects and actions with uncertain outcomes. We show that the latter can, in theory, be viewed as a special case of the former but that to do so requires one to sacrifice the simple, single-model representation for one which can distinguish between a proposition and beliefs about that proposition.