This book must begin with the statement that, like all my otherbooks, it is a strictly historical study. It is not an enquiry into ‘theoccult’ in general, which I am certainly not qualified to undertake.It is about what was known as ‘the occult philosophy’ inthe Renaissance. This philosophy, or outlook, was compoundedof Hermeticism as revived by Marsilio Ficino, to which Picodella Mirandola added a Christianised version of Jewish Cabala.These two trends, associated together, form what I call ‘theoccult philosophy’, which was the title which Henry CorneliusAgrippa gave to his highly influential handbook on the subject.There has been a tendency in modern studies to concentrateon the Hermetic side of the occult philosophy, a tendency towhich I may myself have contributed in my other books. Yet Ihave always insisted that the philosophy, or the movement,should be called ‘Hermetic–Cabalist’, not solely ‘Hermetic’, andI devoted a chapter in my book Giordano Bruno and the HermeticTradition to an attempt to expound Pico’s addition of JewishCabala, in a Christianised form, to Ficino’s Hermeticism.