Is Eriugena an Idealist?

Filipa Afonso (Universidade de Lisboa)

Filipa de Almeida Afonso (Universidade de Lisboa)

“Is Eriugena an Idealist?”

University of Lille, May 23, 2025

Salle Froissart, 2-4 pm

We are pleased to announce that Filipa de Almeida Afonso (Universidade de Lisboa) will deliver a public lecture titled “Is Eriugena an Idealist?” (see abstract below). The lecture will take place on Friday, May 23, 2025, from 2 to 4 pm in Salle Froissart at the University of Lille. 

The event will be held in a hybrid format, allowing for both in-person and online participation. To register for online attendance, please send an email to [email protected], including your first name, last name, and the email address you will use to connect to the lecture.

The lecture is part of the international collaboration project between the Philosophy departments of the University of Rome La Sapienza and the University of Lille (UMR-CNRS 8163 STL), History, Prehistory, and Counter-history of Idealism: Ancient and Contemporary Perspectives. The project investigates, both historically and systematically, the question of the presence, meaning, and forms of Idealism in Antiquity.  Although its main focus is philosophical, the project also addresses key issues in the history of antiquity and literary studies, and its team includes philologists as well as specialists in ancient literature. The project is funded by the Laboratoire Associé International (LAI).

Abstract: In this presentation, I will examine whether John Scottus Eriugena, a 9th century Christian philosopher, can be considered an idealist. To do so, I will begin by addressing the concept of idealism itself – an ambiguous term that encompasses several distinct theories, such as Platonic idealism, empirical idealism, transcendental idealism, and absolute idealism.

Next, I will focus on the main tenets of Berkeleyan idealism—namely, that esse est percipi (to be is to be perceived), and, consequently, that neither material things nor material perceivers exist. With these criteria in mind, I will explore whether Eriugena’s philosophy aligns with idealism. Specifically, I will argue that, based on:

a) the immateriality of God, b) the infinity of God, and c) the rational nature of the human mind,

nothing can exist:

a) materially, b) outside God’s mind, or c) outside the human mind.

To support this argument, I will examine Eriugena’s theory of substance (as a concept of the mind), his understanding of bodies (as coalescences of incorporeal properties, with no subjacent matter), and his theory of place.