EN
In his article 'Ebauches de la volonte dans la tragedie grecque' (1972), Jean-Pierre Vernant deviates around Aristotle and his concepts of voluntary / unvoluntary in order to analyse the Greek Tragics. But he was very influenced by the master commentary of the Nicomachean Ethics by Gauthier and Jolif (1959) in such a way that even the title of his article was issued from that commentary. The present paper argues that this influence was not so right and that it is possible to find in Aristotle and Alexander of Aphrodisias the sources of a libertarian philosophy which is not based on the Stoic or Christian notion of liberium arbitrium.