Studies on Platonic ‘Theoria motus abstracti’ are often focused on dynamics rather than kinematics, in particular on psychic self-motion. This state of affairs is, of course, far from being a bland academic accident: according to Plato, dynamics is the higher science while kinematics is lower on the ‘scientific’ spectrum . Furthermore, when scholars investigate Platonic abstract kinematics, in front of them there is a very limited set of texts . Among them, one of the most interesting undoubtedly remains a passage of Parmenides in which Plato challenges the puzzle of the ‘instant of change’, namely the famous text about the ‘sudden’ (τὸ ἐξαίφνης). Plato’s ἐξαίφνης actually is a terminus technicus and a terminus mysticus at once , in such a way that from Antiquity until today this Platonic concept has been interpreted in very different fashions, either in a physical fashion or in a mystical one. Nevertheless, it has not been analysed how those two directions have been already followed by the Platonic Tradition. So, the aim of this paper is to provide some acquaintance with the exegetical history of ἐξαίφνης inside the Platonic Tradition, from Plato to Marsilio Ficino, by way of Middle Platonism and Greek Neoplatonism. After exposing Plato’s argument of Parm, 156c-157b and its various interpretations (1), I shall investigate the ways by which Middle Platonists (especially Taurus) and Early Neoplatonists as Plotinus and Iamblichus have understood Plato’s use of ἐξαίφνης (2), and finally how this notion had been transferred from kinematics to dynamics in Later Neoplatonism (3).