Mathieu and Simon Hantaï held a series of conferences called the "Cérémonies commémoratives de la seconde condamnation de Siger de Brabant" in 1957. During three weeks, various debates questioned the foundations of western civilisations, the role of the great men and revolutions that shaped the western culture from the Edict of Milan in 313 up to the contemporary breakthroughs in physics and philosophy. Many scholars like essayist T.S. Eliot, philosopher Stéphane Lupasco and scientists took a stand at these conferences. The event was named after the philosopher Siger de Brabant, who played a key role in the 13th-century.