In PHIL 4410 yesterday, I offered Descartes’s argument for dualism:
1. Anything that we can legitimately conceive is logically possible.
2. We can legitimately conceive being conscious without having a brain that’s doing anything. (We can imagine being a disembodied consciousness.)
3. So, it is logically possible to be conscious without having a brain that is doing anything.
4. For any X and Y, if X can exist without Y, then X is not identical with Y.
5. Therefore, consciousness is not identical with having a brain that is doing anything.
It’s an interesting argument, since the premises look pretty plausible. Any thoughts? Where does the argument go wrong?
Here’s another item to consider. Can the same argument be used to show that, say, a computer operating system like Windows is not identical with a computer doing anything? Can we legitimately conceive Windows existing in a world devoid of computers? Or is consciousness seemingly different from a computer operating system in this regard?
(I raise this last point because I often like to compare human consciousness to an operating system: the mind is the software, and the brain is the hardware, and the software is somehow present in the organization and functioning of the hardware, and can’t exist without it. I’m wondering whether this argument points out an important flaw in my comparison.)