In his screen "Cogito Ergo Sum," commissioned by the Sackners, John Furnival used illustrations from the occult works of Robert Fludd, the last of the true Renaisssance men. These include The Solar Logos, The Division of the Waters, The Pythagorean Tetrad, The Diapason Closing Full in Man, The Descent and Re-ascent of the Soul, The Qualities of the Winds, and Chiromancy. -- Source of annotation: Marvin or Ruth Sackner.