Isidoros Katsos: Eriugena’s Notion of Light and His Hexaemeral Sources

In the hexaemeral part of the Periphyseon Eriugena reports on two hermeneutical traditions on the first light of creation. According to the first tradition, attributed to Basil, primordial light is corporeal and of fiery nature. According to the second tradition, attributed to Augustine, primordial light is of intelligible, angelic nature. Based on this report and other passages contemporary scholarship assumes a close acquaintance of Eriugena with Basil’s Hexaemeron. The purpose of this paper is to put the latter assumption under scrutiny. My argument proceeds in two steps. First, I compare Eriugena’s report with Basil’s own theory of light in the Hexaemeron. The comparison shows that the corporeal theory of light reported in the Periphyseon deviates significantly from Basil’s own theory. In a second step, I investigate whether Eriugena’s report is mediated through other sources. I here compare the Periphyseon with corporeal theories of light in Augustine, Ambrose, Gregory of Nyssa and a hexaemeral source available to John Damascene. The comparison now yields positive results: if one reads Basil through the mediation of such theories one may end up indeed with the report in the Periphyseon. If my argument is correct, the current scholarly assumption about Eriugena’s thorough knowledge of Basil’s Hexaemeron needs to be reconsidered. As far as the interpretation of primordial light is concerned, Eriugena did not have direct access to Basil’s own theory and if he did, he understood very little of it.