Chisholm published an extraordinary number of journal articles and reviews. A short discussion of some of the most important of these is included below in Section 13. He also edited, co-edited, and translated several works of others. Among the most important of the books written by Chisholm are: Perceiving: A Philosophical Study [PPS], Theory of Knowledge ([TK1], [TK2], and [TK3] for first, second, and third editions), Person and Object: A Metaphysical Study [P&amp;O], The First Person: An Essay on Reference and Intentionality [FP], The Foundations of Knowing [FK], Brentano and Intrinsic Value [B&amp;IV], On Metaphysics [OM], and A Realistic Theory of Categories: An Essay on Ontology [RTC].