Elements of Theology

Proclus's masterwork of systematic Neoplatonist metaphysics, written in the style of Euclid's Elements with 211 numbered propositions each followed by proof; covers the procession of reality from the One through henads, intellect, soul, and nature; the most rigorous and complete systematic philosophy produced in late antiquity.

The culminating systematic statement of ancient Neoplatonism; its geometric axiomatic method influenced medieval scholasticism; the Liber de Causis, derived from it, was one of the most important philosophical texts in the Latin Middle Ages — wrongly attributed to Aristotle until Aquinas corrected this; shaped Aquinas's understanding of participation.