The where and what of cognition: The untenability of cognitive agnosticism and the limits of the Motley Crew Argument

1. Cognitive Extension and Cognitive Agnosticism According to classical cognitivism, cognitive processes are a special kind of computational processes over (symbolic or subsymbolic) representations. In the case of humans, these processes and representations seem to be found in and only in the brain—maybe not necessarily so, but arguably as a contingent matter of fact (Adams & Aizawa, 2001, 2008). Such a view squares nicely with, although it does not entail, what Susan Hurley (1998, 2001) dubbed the “sandwich model of cognition,” according to which cognition is the intracranial “filling” between perceptual input from and behavioral output to the world. Famously, Clark & Chalmers (1998) suggested a radical alternative to intracranialism. Cognitive processes, they held, can (and at least sometimes do) extend beyond the brain into the extracranial parts of the body and the extrabodily parts of the environment. This hypothesis of cognitive extension is best understood as a claim about the location of the material realizers of cognitive processes: while intracranialists locate the realizers of cognitive processes within the bounds of the skull, advocates of cognitive extension hold that cognitive processes can be materially realized (partially) by processes beyond the skull or skin.