This text is the result of the author's completion of a course in Social Sciences (UFMS) in 2011 and aims to recapitulate the themes addressed in some of the works of Cornelius Castoriadis, who is still unknown to a large part of academia worldwide, but is certainly one of the greatest thinkers of the 20th century. Author of 'The Imaginary Institution of Society' and the volumes of 'Crossroads of the Labyrinth', he always brings up the question of political autonomy, imagination not as mere fantasy and creation in order to think about Being. To ignore Castoriadis is to give up reflective thought, and that is the importance of this work.