In the book "What is this thing called Sarkozy?" Alain Badiou suggests calling "communist hypothesis" what has animated - from the French Revolution onwards - revolutionary politics or politics of emancipation. The verdict that official history attempts to impose is that all attempts to realize this hypothesis have ended in tragic failures, while the hypothesis itself has been invalidated by History.

This book aims to directly examine the famous historical proof of this "failure" through three fundamental examples: the Paris Commune, the Cultural Revolution, and May '68. It argues that, as is equally true in politics and science, the local failure of an attempt does not give us the right to avoid the problem to which this failure proposed a solution. It suggests that today we must imagine new solutions to the problems encountered by this experimentation. This is precisely what the last text of this volume does, which was delivered in London in March 2009 at a significant conference titled "The Idea of Communism".