Proclus was born in 412 in Byzantium in a Lycian family, still faithful to the old Hellenic religion in a society already dominated by Christianity. After Syrianus' death, he became the head of the school and thus 'successor of Plato', a position he held for almost fifty years until his death in 485. This chapter focuses on his theological metaphysics. It follows, as it main inspiration, the Elements, this superb monument of theological metaphysics, wherein Proclus himself is surprisingly sober and rational, and never introduces proper names of gods. Besides his commentaries Proclus owes his reputation mainly to his two great systematic works, the Elements of Theology and the Platonic Theology. Proclus contributed much more to the formation of the Platonic tradition in the Middle Ages than Plotinus. Proclus' speculations on the triadic circle of remaining, procession and return fascinated Hegel.