Internalism and the explanatory role of narrow content
The central problem addressed by this thesis is how narrow content can be genuinely representational and relate to the individuation of mental representations. A second problem relates to the explanatory role of narrow content. The challenge facing the proponent of narrow content is that externalism is the standard position with regard to representation, individuation, and explanation, and it is often held that narrow content is either incoherent or explanatorily redundant. To this end, I defend a version of a two-component theory of content which accepts that wide content is relatively uncontroversial but holds that narrow content has an important role to play. The thesis is divided into two main parts. In part one I focus on the problem of representation and the individuation of mental representations. In Chapter 1 I consider two of the main accounts of wide content from Putnam (1975) and Fodor (1994) and show that in each case there is a notion of narrow content that is compatible with the externalist approach to representation. In particular, I discuss versions of narrow content associated with two-dimensionalism (Chalmers 2003; Jackson 2003a) and radical internalism (Crane 1991; Segal 2000), among other views (e.g. Prinz 2000; Kriegel 2008), and highlight important objections to these existing accounts of narrow content. In response to these problems, I defend a pluralistic view of narrow content according to which there are two main forms of narrow representation, and contend that this account can be systematically supported by understanding the supervenience claim made by the internalist, the kinds of properties represented by mental representations, and the nature of the underlying mental representations that bear narrow content. I then show that this account of narrow content has the resources to respond to a common objection to narrow content (Lepore & Loewer 1986; Block & Stalnaker 1999). In support of this approach to narrow content I show in Chapter 2 that internalism is consistent with recent work on concepts, and in particular with concept pluralism (Laurence & Margolis 1999; Weiskopf 2009) – the view that concepts are comprised of a variety of conceptual structures. I argue that such conceptual structures can be coherently individuated by the narrow contents outlined in Chapter 1, giving rise to an internalist version of concept pluralism. I support the internalist construal of concept pluralism by identifying problems with externalist versions (Laurence & Margolis 1999) and responding to objections to narrow content (Weiskopf 2007). In Chapter 3 I develop an extended critique of social externalism (Burge 1979; Goldberg 2002), and accounts of perceptual psychology (Egan 2009; Burge 2010), both of which purport to have anti-internalist consequences for the individuation and nature of mental representations and provide a challenge to the account of narrow content and mental representations developed in Chapters 1 and 2. In part two, I defend the explanatory role of narrow content. In Chapter 4 I contend that the truth conditions of propositional attitude ascriptions may relate to the narrow contents expressed by attitude ascribing sentences. To show this, I defend a Fregean theory of attitude ascriptions and consider two objections (Soames 2002; Travis 2008) to Fregean accounts that would block the relevant semantic role of narrow content. In addition, I show how this account provides a basis for rejecting two externalist arguments (Putnam 1975; Burge 1979) that rely on assumptions about the nature and role of attitude ascriptions. I contrast this account with existing internalist accounts (Segal 2007; Chalmers 2007), and show how it provides a response to Soames’ (2002) Perfect Earth objection. In Chapter 5 I critically assess two existing accounts of the role of narrow content in psychological explanations of behaviour (Jackson & Pettit 1988; Fodor 1991), focusing on objections raised in connection with proximal causes (Burge 1995) and explanatory generality and causal relevance (Yablo 2003). In response to these objections, I develop an alternative approach which appeals to the rational role of reasons (Davidson 1963; McDowell 2006), and contend that only narrow content can provide a suitably rational explanation of behaviour. I show how this provides a response to the objections raised, and how the appeal to reasons provides a basis for rejecting Fodor’s (1994) more recent externalist account of behaviour.