 One possible reason for the persistence of scientific debates over nativism is that researchers approach psychological development with different explanatory interests. This idea was defended by Peter Godfrey-Smith (1996), who distinguished between “externalist” and “internalist” modes of explanation in biology generally. Externalists “explain properties of organic systems in terms of properties of their environments”; whereas internalists explain, “one set of organic properties in terms of the other internal or intrinsic properties of the organic system” (1996, 30 quoted in Cowie 1998, 16). Nativism can be viewed as an internalist mode of explanation in that it focuses on internal (e.g. genetic) contributions to development while setting aside environmental influences. Conversely, anti-nativists like Kuo or Lehrman focus on certain “external” (e.g. environmental) factors. On this view, the two approaches are not in conflict. Ultimately, it comes down to the interests of an investigator where to place explanatory emphasis.