Thomas Nagel

Nagel's 1974 paper What Is It Like to Be a Bat? argues that consciousness has a subjective character that objective physical description can miss. The bat example matters because echolocation is a real sensory system very different from human vision.

Nagel is more careful than that: he argues that current physicalist explanations do not capture what subjective experience is like. His target is reductive explanation that leaves out the first-person point of view.

Bats are mammals, so it is natural to think they have experience, but they navigate heavily by echolocation. That makes them close enough to take seriously and different enough to show the limits of human imagination.

His 1974 paper became a standard reference point for debates about qualia, reductionism, and the hard problem of consciousness. Philosophers such as Daniel Dennett and David Chalmers discuss Nagel when arguing about whether subjective experience can be fully explained by science.