Artificial Brains May Pose a Startling Ethical Dilemma

Four decades ago,philosopher Hilary Putnam described a famous and frightening thought experiment: A “brain in a vat,” snatched from its human cranium by a mad scientist who then stimulates nerve endings to create the illusion that nothing has changed. The disembodied consciousness lives on in a state that seems straight out of The Matrix, seeing and feeling a world that doesn’t exist.  Though the idea was pure science fiction in 1981, it’s not so far-fetched today. O