ABSTRACT
"In brief all things," wrote Sir Thomas Browne in the Religio Medici 16, "are artificial." One of the interesting thinkers in this regard is the Florentine Platonist Marsilio Ficino, who produced some of the age's most arresting analyses of the artfulness, and thus of the structure, of both human and daemonic nature by implication of their capacities to be moved and to be acted on. In order to understand Ficino's psychology—both of human beings and of daemons—and his speculative ideas concerning the soul's various faculties, this chapter first briefly considers some of the mathematical issues confronting him in Plato. The habitus of the spirit, the hypotenuse of the spirit, would be subject a fortiori to expressly mathematical manipulation—especially to the manipulation of human and daemonic geometers, those skilled above all others in the understanding of planes and surfaces.
