Brains in a Vat

$0 - B


An Old Friend
Skepticism about the character of the external world has been a perennial philosophical problem. A 20th century version of the problem, presented in Hilary Putnam's Reason, Truth, and History, proposes this scenario: While you were sleeping last night, an evil scientist sneaked into your room, anesthetized you, kidnapped you, and took you back to her laboratory. Once there, the scientist removed your brain, put it in a vat, and hooked it up to a sophisticated computer with a remarkable program that allows it to feed your nerve endings signals that duplicate the sensory impulses that usually inform your brain about what your body is doing and where you are. You wake up in what looks like your body, in what looks like your bed, put on what appear to be your slippers, and go about what appears to be your normal life. Since everything looks the same to you, you never suspect that in fact you are just a Brain-in-a-Vat, being fed fake signals that make it seem like everything is normal. The $64 million dollar question for philosophers is, of course,