Reaching Into the Unknown: Actions, Goal Hierarchies, and Explorative Agency

Action is widely characterized as possessing a teleological dimension. The dominant way of describing goal-directed action and agency is in terms of exploitation, i.e., pursuing pre-specified goals using existing strategies. Recent theoretical developments emphasize the place of exploration, i.e., discovering new goals or acquiring new strategies. The exploitation-exploration distinction poses questions with regard to goals and agency: Should exploration, as some authors have suggested, be regarded as acting without a goal? We argue that recognizing the hierarchical nature of goals is crucial in distinguishing the two kinds of activity, because this recognition prevents the claim that exploration is goal-free, while allowing for a homogeneous account of both exploitative and explorative actions. An action typically causes relatively low-level/proximal (i.e., sensorimotor, immediate) and relatively high-level/distal (i.e., in the environment, at a wider timescale) outcomes. In exploitation, one relies on existing associations between low- and high-level states, whereas in exploration one does not have the ability or intention to control high-level/distal states. We argue that explorative action entails the capacity to exercise control within the low-level/proximal states, which enables the pursuit of indeterminate goals at the higher levels of a goal hierarchy, and the possibility of acquiring new goals and reorganization of goal hierarchies. We consider how the dominant models of agency might accommodate this capacity for explorative action.