Abstract

Apparently alone among medieval Christians, Eriugena argues that all life is immortal. He relies on Plato’s Timaeus as his primary source for this claim, but he modifies the argument of the Timaeus considerably. He turns Plato’s cosmic soul into the genus of life, thereby taking a treatise that originally dealt with cosmology and using it to explore the ontological significance of definition. All species that fall under the genus of life must be immortal, because a mortal species would contradict the genus. No later medieval author would take up Eriugena’s arguments explicitly, although Aquinas comes close. The two thirteenth-century thinkers to address universal immortality seriously—Aquinas and Bonaventure—argue against it, but they are more faithful than Eriugena himself to a literal reading of the Timaeus.