Action as a Reaction Psychological and Logical Issues in the Early Stoic Theory of Action

In this paper I would like to offer a contribution to the explanation of the Stoic thesis according to which human action is a reaction to a psychic act of a logical and linguistic type. Interpreters fairly often use the notion of 'reaction' with regard to the Stoic theory of praxis in order to emphasize that action is the response to a sensory stimulus and to a certain content of the imagination, or representation (phantasia).