I believe that Rand was wrong about every perception always being of an external existent.Even when discussing introspection, she says:" Introspection is a process of cognition directed inward - a process of apprehending one's own psychological actions in regard to some existent(s) of the external world." Monitoring your own heartbeat and breathing would be counter-examples. That said, this chapter is a succinct taxonomy of consciousness processes of evaluation, love, affection, knowledge, imagination, thought, and emotion. This is important as another method of bridging epistemology to metaphysics.

As throughout, Rand repeats the formation of concepts on this topic in this chapter by the process stated in the opening (page 11) of abstracting the essential differences shared by two or more referents and uniting them by abstracting that characteristic without regard to measurement.

(Still waiting for your comments on Chapter 3, as well as yours here for Four.)