The explanatory breadth of pushmi-pullyu representations

The pushmi-pullyu representation (“PPR”) is a non-conjunctive representation with both descriptive and directive contents. Introduced by Millikan, the PPR is supposed to aid in explaining how organisms adapt behavior to environmental variance in the absence of intermediate inference. Until recently, it has led an uncontroversial theoretical life. However, Artiga has suggested that the PPR postulate conflicts with Millikan-style teleosemantics and, as a consequence, the PPR postulate should probably be set aside. I suggest here that the theoretical motivations for the PPR are independent of any specific theory of naturalized content. If Artiga is right about the PPR’s incompatibility with Millikan-style teleosemantics, then that only reveals the inadequacy of Millikan-style teleosemantics. The PPR has a clear role to play in explaining the primitive systems that dominate the biosphere. However, Millikan did not want to limit the explanatory utility of the PPR to primitive systems but suggested that it has explanatory work to play in the animal signaling of complex organisms, Gibsonian affordances, as well as with distinctively human mental life and language. Contra Millikan, I suggest that the PPR has no or at best a very limited explanatory role to play in such cases. Further, the non-inferential feature of the PPR suggests that it should be understood at best as a marginal or borderline representation.