Pretty interesting interview. Marshall and Mandik discuss consciousness, philosophy of mind, science fiction, the matrix, and a variety of other issues. I was struck by this remark in particular by Mandik:
“All those early contemplations of jacking into the matrix and jockeying around in cyberspace have made me permanently allergic to stuff like direct realism and the embodied cognition movement. I can’t shake the conviction that brain in a vat that is a perfect intrinsic duplicate of my brain is going to be a perfect mental duplicate.”
This remark puzzles me. For surely the “vat” of the brain can be understood as a kind of body, supplying nutrients to the brain. So the possibility of a brain in a vat doesn’t undercut the thesis that all cognition is embodied. As for the brain-in-a-vat being a “perfect mental duplicate”, wouldn’t a more plausible claim be that the brain-in-a-vat would fairly similar but not identical? “Perfect mental duplicate” seems like a stretch. But let’s suppose that every input to the brain was simulated perfectly. Wouldn’t it then be a perfect duplicate? Well, those simulated inputs would have to mimic the ways in which diffuse clouds of chemicals influence the brain, as well as simulate patterns of astrocytal modulation. I don’t think a perfect duplicate would be merely a simulation of neuronal firing rates with electrical brain interfacing. That would be an imperfect but close simulation. And if you could achieve a perfect simulation of diffuse chemical input, astrocytal modulation, and all other subtle but non negligible modulatory influences, then it seems like the chemical-input generator and host of modulators would just be a kind of artificial body. So I’m not sure the embodied cognition thesis is really threatened by brains-in-vats. Sure, there might be some overly strong forms of the embodied cognition thesis (thinking of Alva Noe) that don’t support even the idea of an imperfect simulation being minded in a similar way to normals. But we shouldn’t always think in terms of the strongest forms of any given thesis. Moreover, I have been developing this idea about organisms without nervous systems having primitive mental states. If this is right, then there is a mindedness intrinsic to the activities of cellular organisms, not just organizations of neural cells. Accordingly, the brain-in-a-vat will be missing all of that nonneural mindedness, and would thus be a similar but imperfect duplicate.