In his new book Oliver Sacks reveals how an amphetamine trip led to his lifelong obsession with the strangest experiences of the human mindby Adam Kirsch / October 17, 2012 / Leave a comment
Published in November 2012 issue of Prospect Magazine
Two brains: few authors have influenced the popular imagination of mental illness as much as Sacks
Ask a philosopher to name the most influential philosophical essay of the last half-century and there’s a good chance he will choose Thomas Nagel’s 1974 paper “What Is It Like to Be a Bat?” The point of Nagel’s argument is not that there is anything especially exciting about bats’ mental lives, but simply that there is no way for a human being to understand how bats—or, for that matter, any other creature—experience the world. What would it be like to know the world not through light and colour, but through sound and echo? The answer cannot be found by opening up a bat’s skull and measuring the electrical pulses in its tiny brain.
Nagel’s argument suggests there is an irreducible gulf between the human brain and the human mind. The mind may be created by the brain but there is no way to deduce the nature of consciousness from even the most complete neural map. The old mind-body problem, which bedevilled Descartes in the 17th century, does not disappear even in an age of neurological wizardry like our own. “Without consciousness,” Nagel writes, “the mind-body problem would be much less interesting. With consciousness it seems hopeless.”
The only way to find out what it’s like to be a bat would be to ask a talking bat. But what if you could find a human being whose consciousness, whose experience of the world, was so radically different from the norm that he is in some sense inhuman, or superhuman? What if a human brain, through some disease, stroke, or injury, produced a qualitatively different kind of mind, yet left its possessor still human enough to tell the world—with the help of an interpreter—what his world felt like?