What is externalism?

The content of the externalist thesis about the mind depends crucially on how we define the distinction between the “internal” and the “external”. According to the usual understanding, the boundary between the internal and the external is the skull or the skin of the subject. In this paper I argue that the usual understanding is inadequate, and that only the new understanding of the external/internal distinction I suggest helps us to understand the issue of the compatibility of externalism and privileged access.