The theme of the conference Origeniana Undecima is 'Origen and Origenism in the History of Western Thought'. This theme includes a number of sub-themes, such as the reception of Origen and Origenism in philosophy and theology, from the earliest reception in the third and fourth centuries through the Middle Ages to the most recent reception in the 20th century; the philological work on Origen's texts; the use or rejection of Origen's exegetical principles etc.