Jim talks with Nicholas Humphrey about the ideas in his 2023 book Sentience: The Invention of Consciousness. They discuss the distinction between sentience & consciousness, access consciousness vs phenomenal consciousness, terminology in consciousness studies, ring-fencing theories, Nicholas's early experiments with phosphenes, the discovery of blindsight in monkeys, his relationship with Helen the monkey, color preferences in monkeys, sensation vs perception, realism vs illusionism, consciousness as art, the concept of "ipsundrum," the evolution of consciousness as "all or nothing," the Fermi paradox & the uniqueness of consciousness, qualophilia, consciousness in birds & mammals, theory of mind in different species, and much more.