It outlines a scenario in which a person’s brain is removed from the body and suspended in a vat of life-sustaining liquid, and connect its neurons by wires to a supercomputer that would provide it with electrical impulses identical to those a brain normally receives

Then, the computer would then be simulating the world and the appropriate responses to the brain’s own output and the “disembodied” brain would continue to have perfectly normal conscious experiences, such as those of a person with an embodied brain, without these being related to objects or events in the real world.

Related to virtual worlds and the Matrix

Could we say/think/believe that we are brains in a vat? Putnam states that this argument is false as it is self-refuting

  1. Assume we are brains in a vat
  2. If we are brains in a vat, then “brain” does not refer to brain, and “vat” does not refer to vat (via CC)
  3. If “brain in a vat” does not refer to brains in a vat, then “we are brains in a vat” is false
  4. Thus, if we are brains in a vat, then the sentence “We are brains in a vat” is false (1,2,3)

Are the things that BIVs refer to the same things that we as real people refer to? That is, if the relation is not grounded in the same thing, are the semantics still the same