Frances Yates 
The Occult Philosophy in the Elizabethan Age [PDF ebook] 

First published in 1999. This is volume VII of ten of the collected works of Frances Yates. This book is a strictly historical study, not an enquiry into ‘the occult’ in general, which I am certainly not qualified to undertake. It includes what was known as ‘the occult philosophy’ in the Renaissance. This philosophy, or outlook, was compounded of Hermeticism as revived by Marsilio Ficino, to which Pico della Mirandola added a Christianised version of Jewish Cabala. These two trends, associated together, form what Yates calls ‘the occult philosophy’.