 In one of their experiments the authors manipulated the way in which birdsong was described. In one condition, birds were described as “learning” their song. In another condition, the same acquisition process was described in neurological terms: birds were described not as learning their songs, but rather as acquiring songs through specific neurological interactions with the environment. Recall that primitivism (Section 2.3) predicts that a trait described as “unlearned” should be less likely to be seen as innate than one which is described as the result of a sub-personal, neurological process. The fact that subjects responded no differently to the “learned” versus “neurological” versions of the questionnaire (regardless of whether they were scientists or lay persons) contradicts this prediction of primitivism. It is also interesting to note that Knobe and Samuels (2013) found an effect of moral “valence” on innateness judgments. If a behavior was morally unacceptable, subjects were less likely to judge it as innate than if it was morally good. This result ties in with a broader literature on the influence of moral valence on all manner of folk judgments (Knobe and Mendlow 2004; Cushman, et al. 2008; Petit and Knobe 2009). Finally, Knobe and Samuels (2013) included another version of the birdsong questionnaire in which subjects were told how different vignettes varied from one another, while also prompting subjects to justify their responses. This was interpreted by the authors as a “reflective” condition, with the aim of prompting subjects to answer more systematically. Knobe and Samuels (2013) report that subjects responded more systematically under the “reflective” condition than they did under the unreflective one, suggesting that even naïve subjects will be less likely to equivocate in their judgments if they are prompted to do so (see Linquist 2018 for a discussion of this result). All of the experiments reported in this section are suggestive and offer an interesting example of how empirical methods can be used to analyze both folk and scientific concepts. Hopefully other researchers will be inspired to carry this work forward.