Generic statements express generalizations about categories. Current theories suggest that people should be especially inclined to accept generics that involve threatening information. However, previous tests of this claim have focused on generics about non-human categories, which raises the question of whether this effect applies as readily to human categories. In Experiment 1, adults were more likely to accept generics involving a threatening property for artifacts, but this negativity bias did not also apply to human categories. Experiment 2 examined an alternative (...) hypothesis for this result, and Experiments 3 and 4 served as conceptual replications of the first experiment. Experiment 5 found that even preschoolers apply generics differently for humans and artifacts. Finally, Experiment 6 showed that these effects reflect differences between human and non-human categories more generally, as adults showed a negativity bias for categories of non-human animals, but not for categories of humans. These findings suggest the presence of important, early-emerging domain differences in people's judgments about generics. (shrink)

What role does the concept of naturalness play in the development of scientific knowledge and understanding? Whether naturalness is taken to be an ontological dimension of the world or a cognitive dimension of our human perspective within it, assumptions of naturalness seem to frame both concepts and practices that inform the partitioning of parts and the kinding of kinds. Within the natural sciences, knowledge of what something is as well as how it is studied rely on conceptual commitments. These conceptual (...) commitments shape how entities and processes are categorized _as_ natural depending on how naturalness has been understood within that discipline. In this paper, I explore how commitments to naturalness shape different conceptualizations of what were previously and what are now considered to be fundamental parts in plant morphology. Relying on an historically informed epistemological approach, I trace the origins and development of models of plant morphology from (1) Goethe’s classical LEAF-ROOT-STEM archetype model; (2) Agnes Arber’s revisions to Goethe’s model reconceived in her partial-shoot theory of the leaf; and (3) Rolf Sattler’s proposal for a processual model of plant morphology. These influential models posit ontologically and epistemologically inconsistent conceptualizations of the natural fundamental parts of plants and how they are related to each other. To explain what this inconsistency means for the concept of naturalness and the role it plays in plant morphology, I suggest naturalness might best be conceived of as a contextually bound classificatory concept that is made and remade through its operationalized use within a model, theory, set of practices, or discipline. (shrink)