This monumental treatise ›Über die immerwährende Philosophie‹ (On Perennial Philosophy), written by the Vatican librarian Agostino Steuco (1496–1548), first published 1540 in Lyon, is deemed as one of the most influential works of the early modern historiograhy of philosophy and theology. In this treatise, based on a Christian interpretation of Platonism as defined by Marsilio Ficino and Giovanni Pico della Mirandola, Steuco tried to bring together the wisdom of the first creation and of antiquity and to prove their conformity with the wisdom of Christianity.