Simplicius’ project of harmonizing previous philosophers deserves to be taken seriously as both a philosophical and an interpretive project. Simplicius follows Aristotle himself in developing charitable interpretations of his predecessors: his distinctive project, in the Neoplatonic context, is the rehabilitation of the Presocratics (especially Parmenides, Anaxagoras and Empedocles) from a Platonic-Aristotelian perspective. Simplicius’ harmonizations involve hermeneutic techniques which are recognisably those of the serious historian of philosophy; and harmonization itself has a distinguished history as a constructive philosophical method.