"Freedom is not possible without authority (otherwise it becomes chaos) and authority not without freedom (otherwise it becomes tyranny)." This demand of Stefan Zweig for political reason and humane tolerance forms the core of this book written in 1936 "against all forces of violence". By means of historical events, he shows the dangers and evils of his own time in a particularly clear mirror image, thus at the same time giving his admonition validity for all times. Of all his contemporaries, the French humanist Sebastian Castellio was the most decisive in his opposition to Jean Calvin, the Geneva Reformer who despotically administered doctrine and power. Above all, however, he takes the side of the Spanish doctor Michael Servet, accused of blasphemy and finally executed at the stake. After the execution of this judgement the fight seems to be decided.