Nicholas Keynes Humphrey (born 27 March 1943) is an English neuropsychologist based in Cambridge, known for his work on evolution of primate intelligence and consciousness. He studied mountain gorillas with Dian Fossey in Rwanda; he was the first to demonstrate the existence of "blindsight" after brain damage in monkeys; he proposed the theory of the "social function of intellect". He is the only scientist to have edited the literary journal Granta.