Chisholm steadily thought there is something fundamentally right about Brentano’s Thesis — the idea that the psychological somehow involves intentionality, and that in this respect it is unlike the purely physical. Chisholm discussed this idea in his early paper “Sentences about Believing” (1955–6). He discussed it again in Chapter 11 (“Intentional Inexistence”) of [PPS]. A summary statement of the view can also be found in Chisholm’s article “Intentionality” (1967c). Chisholm returned to this topic in Part IV (Chapters 10–14) of [OM].