The pervasiveness in psychological literature of the assumption that mental events and psychology in general occur within the person—henceforth the psychological ‘interior’— is introduced and the received view of its historical origin is presented. This account is challenged and classical historical source material from the period 100 to 400 CE is interpreted in relation to factors of literary practice and related issues (mode of reading, authority and format of text, mode of writing, and author's motivation). It is concluded that the ‘interior’ that emerges in the reflexive discourse of Imperial Rome develops in tandem with changes in literary practices and that there is consequently substantial evidence for positing an intimate relationship between these practices, subjective experience, and reflexive discourse. © 2008Wiley Periodicals, Inc.