Abstract
This essay explores the implications of a commonly held ancient and medieval belief that human memory and invention are, if not exactly the same, the closest thing to it. In order to create, in order to think at all, human beings require both a well-provisioned stock of memory-held knowledge and some mental tool or machine, an engine which lives in the intricate networks of their own memories. In the verbal arts of the trivium students learned the basic principles of memory training: the need for divisio, the need to make a clear, distinct location for each piece of memorized content, and the need to mark items uniquely for secure recollection. Frequently these mental structures took the form of images. Evidence for such memorial and compositional images is common: I focus on a few representative types, including the sermon-related Cherub figure of the later Middle Ages, and accounts by Cassiodorus and others of scholars, even when blind, using their highly structured memories to compose new work.