Abstract

This thesis is a study of the philosophical system of a little-studied, but important medieval thinker, John Scottus Eriugena , concentrating on his Periphyseon . ;I argue that Eriugena's system of nature must be approached through an investigation of his epistemology and general philosophy of mind. Instead of beginning with his fourfold classification of Nature, as most commentators have done, I begin with Eriugena's concept of the mind and its dialectical operations , and continue with an examination of his anthropology , and his concept of self-knowledge , before turning to his relativist ontology of being and non-being . Chapter Seven examines Eriugena's fourfold division of Nature in the light of the earlier chapters. ;Against some recent commentators, I argue that Eriugena should not be interpreted solely from within the framework of the Latin-Augustinian metaphysical tradition of the early Middle Ages, that it was his sympathy for Greek Christian Neoplatonism which led him to develop an idealist philosophical outlook . Eriugena synthesises the Greek Eastern and the Latin Western traditions into a profound and original philosophical system. ;I show further that Eriugena "deconstructs" Latin metaphysical realism in favour of his own "me-ontology" or "meta-ontology," inspired by the Greeks. He produces the most detailed account of non-being between Plato's Parmenides and the phenomenologies of nothingness of Heidegger and Sartre. ;The summit of Eriugena's system is infinite Non-being, or infinite self-identical subjectivity. This philosophy bears strong similarities to post-Kantian critical philosophy, especially the Idealism of Fichte, Schelling and Hegel. My interpretation thus agrees with the nineteenth-century Idealist reading of Eriugena. At the same time, it suggests the implications of Eriugena's idealism for the interpretation of certain modern philosophies