This chapter focuses on one aspect of practical cognition — plan-construction. Human plan-construction is generally based on means-end reasoning. Means-end reasoning is concerned with finding the means for achieving goals. The basic idea is a simple one: to achieve a goal, we consider an action that would achieve it under some specified circumstances and then try to find a way of putting ourselves in those circumstances in order to achieve the goal by performing the action. Putting ourselves in those circumstances becomes a subgoal. The idea is to work backward from the goal through subgoals...

This chapter focuses on one aspect of practical cognition — plan-construction. Human plan-construction is generally based on means-end reasoning. Means-end reasoning is concerned with finding the means for achieving goals. The basic idea is a simple one: to achieve a goal, we consider an action that would achieve it under some specified circumstances and then try to find a way of putting ourselves in those circumstances in order to achieve the goal by performing the action. Putting ourselves in those circumstances becomes a subgoal. The idea is to work backward from the goal through subgoals until we arrive at subgoals that are already achieved. The resulting sequence of actions constitutes a plan for achieving the goal. A precise logical theory of plan-construction is formulated that completely characterizes means-end reasoning.