Refl ections on Walter Chatton’s Reportatio and Lectura

Walter Chatton’s Reportatio has been dated to 1322-23, possibly at London, and his Lectura either as a revision of bachelor lectures given earlier at Oxford, or given after 1323. Stephen Brown has shown that material in Chatton’s Lectura dates to 1323-1324 when Chatton and Ockham were disputing in the same place, presumably London, before Ockham left England forever. The present article shows how arguments dating to one place and time can be used in a later work, and should not be used to date that work.