englischThe concepts of action and passion are recognized as categories of being by Aristotle, and henceforth discussed as such by later ancient philosophers ; they were crafted to understand the way becoming things interact with one another - in turn acting upon and being acted upon, thus causing effets on many other things whilst being subjected to the effects caused by others. Plato has not been accredited with a major role in the history of these concepts, possibly since he has often been perceived, for instance by his pupil Aristotle, as a philosopher who favours the intemporality of invisible, intelligible objects over the instability of becoming things. But this may not be so simple. Perhaps Plato appealed to invisible principles in order to further understand how moving things behave. Aristotle's delvings into the problems of activity and passivity might indeed be more faithful to Plato than commonly perceived.
This book puts forth Plato's philosophy of action and passion, exposing their limits and moving on to a general theory of the interaction of bodies, of souls and of cities - all things in motion that exist for Plato within the universe. A philosophy of the becoming of all things is at work in Plato's dialogues, and it manifests the natural unity of all forms of movement, whether cosmic, animal, human or social.