Proceedings of the Annual Meeting of the Cognitive Science Society

This paper challenges the widely accepted claim that "classical" cognitive architectures can explain the systematicity of cognition (Fodor & Pylyshyn, 1988). There are plausible ways of rendering more precise the systematicity hypothesis (as standardly formulated) in which it is entailed by classical architectures, and other plausible ways in which it is not. Therefore, it is not a determinate issue whether systematicity is entailed, and hence explained, by classical architectures. The general argument is illustrated in a particular domain, the systematicity of deductive inference. In the case of the capacity to carry out the inference modus tollens, the systematicity hypothesis can be made precise in two ways, one entailed by classical architectures, another which is not. Further, the latter, but not the former, accurately describes the actual empirical phenomenon. Put another way, the clumps that these deductive inference capacities come in are not the clumps that are entailed by classical architectures. Therefore, in this area at least, systematicity considerations count against the classical conception of cognitive architecture.