Abstract

The extended mind thesis is attractive and important to the extent that it expresses a deep metaphysical truth; that is, to the extent that it gives us a new and somewhat surprising account of the nature of mental phenomena. However, as I will argue in this paper, one cannot find a set of plausible criteria to single out the class of extended systems or processes; any choice of criteria appears indeed to be conventionalist and arbitrary. Therefore, the extended mind thesis is metaphysically insubstantial. At most it could amount to an epistemological plea for dynamicist models in cognitive science, albeit in a few, limited cases.