In writing about freedom at the end of the 20th century, in his The Proper Study of Man (1998), Isaiah Berlin would refer to Heinrich Heine’s text entitled De l’Allemagne (literally “From Germany”). This book was written by Heine while he was a refugee in France. This title bears important resemblance to Madame de Staël’s book by the same title, De l’Allemagne, published in 1813. In this text, the writer philosopher Heine warns the French about the Power of Ideas (Macht der Ideen), with power (Macht) being understood also in the sense of violence (Gewalt). Heinrich Heine wrote about how, in the silence of the philosopher’s study, powerful ideas can be born; ideas that have the ability to destroy the whole of civilization. We nevertheless often forget the roots of this idea – an idea that has shaped our world to such a considerable degree. For this reason, it is to these roots that we dedicate the fourth edition of Orbis Idearum.