Composite Subjectivity in Organisms, Organs, and Organizations

This chapter looks at four potential cases of mental combination, to examine what the theory sketched in the previous chapter might say about them. It starts with the “Nation-Brain” thought experiment, originally offered as a reductio ad absurdum of functionalism, where a few billion people agree to collectively simulate a single human mind. It then considers actual human social groups, the ways that they differ from this thought experiment, and the significance of these differences for questions of collective mentality. It next considers the split-brain phenomenon, where patients with a severed corpus callosum seem at times to exhibit two distinct consciousnesses in one head, and then finally comes back to the ordinary human brain, where two cerebral hemispheres, each capable of supporting consciousness without the other, are able to establish richly unified consciousness through their intact corpus callosum.