Source

  • Clark & Chalmers (1998), The Extended Mind, LIT-097, read in full in NOTE-180 from the authors’ web version; agreement with the typeset Analysis text is unverified.
  • Clark (2005), Intrinsic content, active memory and the extended mind, LIT-403, read in full in NOTE-363.

The argument

Otto’s notebook “plays the role usually played by a biological memory” (§4). On role-functionalism about belief (“What makes some information count as a belief is the role it plays”, §4), Otto believed the museum was on 53rd Street before he looked, as Inga did before she recalled it. Twin Otto, a duplicate “from the skin in” whose notebook says 51st Street, believes otherwise, so “a belief is simply not in the head”.

The features that make the case clear are constancy, direct availability, automatic endorsement and, “arguable”, past conscious endorsement (§5). They are “features of our central case”, not necessary and sufficient conditions. §5 extends the reasoning to other people: in “an unusually interdependent couple” one partner’s beliefs can play the notebook’s role, given “a high degree of trust, reliance, and accessibility” (NOTE-180).

The step from coupling to parthood is carried by role-functionalism, the parity sentence of §2, stated “(so we claim)”, and explanatory simplicity (NOTE-180). Clark (2005): “We did not argue for this principle, except by providing illustrations and defences against counter-arguments” (NOTE-363, p. 2). The thesis concerns material vehicles, not contents (LIT-403, n. 1).

What this does not say

It does not say the conditional holds. Whether coupling of this kind makes a store part of a mind is THEORY-579’s promote_when. Against it stand Adams and Aizawa’s objection that coupling is not constitution (LIT-438, LIT-455) and Rupert’s that the differences Clark sets below the functionalist’s level do explanatory work (LIT-422). THEORY-579 stays Proposed until the record holds an account of constitution that settles it. Nor does this entry say the four features are sufficient, that consciousness extends, or that ordinary tools carry their users’ beliefs.