The Architecture of Cognition: Rethinking Fodor and Pylyshyn's Systematicity Challenge

11. Systematicity Laws and Explanatory Structures in the Extended Mind

The systematicity argument championed by Jerry Fodor, Zenon Pylyshyn, and Brian McLaughlin (Fodor and Pylyshyn 1998; Fodor and McLaughlin 1990) became a magnet for debates over the cognitive architecture, providing an empirically based challenge to those who did not accept classical computationalism. In general, the alternative explanations of systematic patterns that were proposed by connectionist models did not directly challenge the assumption that mental representations are both syntactically and semantically internal, focusing instead on alternative means of achieving compositionality without classical vehicles of content (see, e.g., Van Gelder 1990; Chalmers 1993; Smolensky 1995). However, some recent discussions locate the explanatory structures for such patterns outside the brain. While not always couched in terms of the extended mind theory, proposals by authors such as Menary (2007) and Symons (2001) reconsider the explanations for such patterns to encompass aspects of the linguistic environment. In what follows, I will outline one variety of such an explanation as part of a more general review of the ways in which the extended mind theorist might address the systematicity challenge. The attempt here is to meet the systematicity challenge as directly as possible, accepting most of the definitions made in the original argument insofar as they can be accommodated in this framework while questioning some underlying assumptions about the nature of representation. The proposed explanation considers the relevant explanatory structures that determine the nature of instances of systematicity laws to be extended, though allowing that the mechanisms that directly support them may be internal to the cognitive agent. This shift of the explanatory burden away from properties that are possessed intrinsically by intracranial mental states can be compared to a similar explanatory strategy employed by Pylyshyn in relation to imagistic 11 Systematicity Laws and Explanatory Structures in the Extended Mind Alicia Coram 278 Alicia Coram phenomenon, and his work provides a useful framework for both understanding and potentially empirically verifying this method of explaining evidence for the systematicity of thought. A brief review of some of the empirical evidence that exists for the systematicity of thought suggests that the patterns that do exist in such cognitive abilities can more easily be accommodated by this explanation. 1 The Systematicity Challenge and the Extended Mind 1.1 The Challenge Fodor’s original construction of the systematicity argument begins with the observation of certain lawlike patterns in cognitive abilities that he claims have the status of psychological laws. His toy examples of the systematicity of thought are by now familiar—the ability to think thoughts such as John loves Mary coexists (ceteris paribus) with the ability to think thoughts such as Mary loves John, and so on for any clusters of similar thoughts. This is captured in the general schema: Ceteris paribus, a cognizer is able to think the thought that aRb if and only if he is able to think the thought that bRa. McLaughlin has clarified that “think the thought” is intended to mean “mentally represent,” and furthermore that mental representations have propositional contents, so the relevant schema can be restated as: “Ceteris paribus, a cognizer is able to mentally represent that aRb if and only if the cogniser is able to mentally represent that bRa” (McLaughlin 2009, 272). This claim is also extended to inferential abilities; however, the systematicity of thought will be the focus of this chapter. Several authors (see, e.g., Schiffer 1991; Cummins 1996; Johnson 2004) have argued that such definitions are uninformative and risk either begging the question regarding the nature and structure of mental states or biasing the identification of systematic patterns toward those most naturally explained by classical computational architectures. However, as McLaughlin notes, the general schema does not commit the advocate of the systematicity argument to anything beyond the claim that the relevant contents “will be related, albeit non-equivalent” (McLaughlin 2009, 254) mental contents. He also rejects the possibility of providing a list of necessary and sufficient conditions identifying the clusters of thoughts that are in fact related by systematicity laws, and he does not believe that such conditions are required to pose a challenge to nonclassicists (ibid., 253). In part, this is because of the controversial nature of theories about propositional Systematicity Laws and Explanatory Structures 279 content, which he argues means that it is “indeed best to identify the thought abilities in question other than by appeal to any hypothesis about what the similarities in propositional-content consist in, for just about any...