How did consciousness evolve? - with Nicholas Humphrey

Find out how consciousness is generated in the human brain - and discover the evidence suggesting some animals are also sentient.


Find out how consciousness is generated in the human brain - and discover the evidence suggesting some animals are also sentient.

Read Nicholas's book 'Sentience: The Invention of Consciousness' here:
Watch the Q&A here:

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Join renowned psychologist and philosopher Nicholas Humphrey as he presents his theory of 'phenomenal consciousness', in full for the first time.

Weaving together leading-edge science and personal breakthrough experiences, Nicholas provides a comprehensive look at the evolution of consciousness. He discusses discovering blindsight in monkeys, hanging out with mountain gorillas in Rwanda, to becoming a leading philosopher of the mind; all leading to a scientific understanding of consciousness and his theory as to how conscious feeling is generated in the human brain.

This theory also provides the foundation for Nicholas' controversial opinion - in contrast to broad scientific opinion - that phenomenal consciousness is only present in warm-blooded creatures such as mammals and birds, and not invertebrates like octopuses and bees, despite their known intelligence.

This lecture was recorded at the Ri on 21 June 2023.

00:00 Intro
03:20 Blind sight – seeing without a visual cortex
09:51 The difference between sensation and perception
11:37 Can consciousness be physically found in the brain?
16:58 How did natural selection lead to sensations?
22:28 How did this lead to consciousness in the human brain?
24:58 What is the point of phenomenal consciousness?
28:14 How human sentience led to theory of mind
30:17 Could animals also be sentient?
33:32 Body temperature and its effect on brain speed
34:45 Evidence for sentience in the animal kingdom
40:40 Mammals and birds show sentience – what about octopuses?
42:25 Can machines ever reach consciousness?
45:05 Could there be sentient aliens?
46:42 The extinction of consciousness on Earth

Nicholas Keynes Humphrey is an English neuropsychologist based in Cambridge, known for his work on evolution of primate intelligence and consciousness. He has been lecturer in psychology at Oxford, assistant director of the Subdepartment of Animal Behaviour at Cambridge, senior research fellow at Cambridge, professor of psychology at the New School for Social Research, New York, and school professor at the London School of Economics.

Humphrey played a significant role in the anti-nuclear movement in the late 1970s and delivered the BBC Bronowski memorial lecture titled "Four Minutes to Midnight" in 1981.

He has written 10 books and received several honours, including the Martin Luther King Memorial Prize, the Pufendorf Medal and the British Psychological Society's book award. He is the only scientist to have edited the literary journal Granta.

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