 Book II, dedicated to astrology, opens with the celebrated image of the magus as the go-between who subjects sublunary world to the stars. The knowledge of the laws, governing how the celestial influences flow down to the earth, enables the magus to collaborate actively with nature, modifying the phenomenal processes. To describe astrological images, attracting astral virtues, Agrippa pillaged the technical details described by Ficino in De vita coelitus comparanda (On Obtaining Life from the Heavens), but he also went back to the medieval tradition.