Professor Raffaele Pettazzoni is one of the most illustrious historians of religion of our time. He belongs to a type of scholar which is unfortunately becoming rare and is perhaps headed for extinction: those who have taken as their specialty the universal history of religion. At first sight such an ambition might seem to pose an impossible task; the historico-cultural field has become so wide that no single mind could pretend to assimilate and master a quantity of documents that is increasing every day. Let us therefore avoid misunderstanding on this point: there is no question of the historian of religions attempting to replace the Americanist, the Sinologist, the Africanist, or to master their knowledge of philology in order to study and interpret the Chinese, Aztec and Bantu religions: it suffices for him to record the results of research carried out by the specialists and to classify and evaluate these results in a perspective which is exclusively his own: that of the general history of religion.