Abstract

The first doctrine Peckham mentions as being under attack is of undoubtedly the TDI, according to which human beings are illuminated by "the unchangeable light" so as to attain the "eternal rules." This language of light and illumination is of course most closely associated with Augustine, but it permeates the entire Christian medieval tradition. Until Aquinas's time the TDI had played a prominent role in all the most influential medieval theories of knowledge, including those of Anselm, Albert the Great, Roger Bacon, and, especially, Bonaventure. However, by the beginning of the fourteenth century the theory had fallen out of fashion. Indeed, the three best philosophers of the scholastic period--Aquinas, John Duns Scotus, and William Ockham--would all reject the theory in its standard form. Even by 1285 supporters of the TDI such as Peckham were evidently feeling rather defensive. It seems entirely plausible to attribute this attitude, in large part, to the influence of Aquinas's views on human knowledge.