Gertler B. Content externalism and the epistemic conception of the self. Philosophical Issues. 2007;17.
Many philosophers accept the following triad of views. (A) Externalism about mental content; (B) internalism about the self; (C) an epistemic conception of the boundary of the self. I argue that this triad, though not incoherent, is unstable. Since we ordinarily delineate the self in epistemic terms, (C) is highly plausible. So we should either reject externalism about mental content (that is, (A)) or allow that the mind extends into the world (and thus reject (B)).