Columbia subject headings:
Color (Philosophy)
Consciousness.
Knowledge, Theory of.
Metaphysics.
Perception (Philosophy)
Skepticism.
Harvard subject headings:
Color (Philosophy)
Consciousness.
Knowledge, Theory of.
Metaphysics
Perception (Philosophy)
Skepticism.
Princeton subject headings:
Color (Philosophy)
Consciousness.
Knowledge, Theory of.
Metaphysics.
Perception (Philosophy)
Skepticism.