1929. Edited, preface, and bibliography by G.R.S. Mead. Contents: On the virtues; On Dialectic; On Matter; Against the Gnostics; On the Impassivity of Incorporeal Natures; On Eternity and Time; On the Immortality of the Soul; On the Three Hypostases that rank as the Principles of Things; On Intellect, Ideas, and Real Being; On the Essence of the Soul; A discussion of Doubts relative to the Soul; On the Generation and Order of Things after the First; On Gnostic Hypostases, and That which is beyond Them; That the Nature which is beyond Being is not Intellective, etc.; On the Good, or the One.