Granularity in taxonomy, time, and space

The objects of language and thought establish the granularity at which cognition operates. Granularity can vary with respect to taxonomic classification, time, and space. One might suppose that basic cognitive operations such as judgments of similarity or mental imagery would be invariant over these changes in scale, but this appears not to be the case. This chapter reviews results from three domains that show how changes in grain lead to changes in the form of cognitive operations. In judgments about object features, small and medium taxonomic scales are heavily depending on an object's parts, but large taxonomic scales are not. In perceiving events on a small temporal scale people pay close attention to actions on individual objects, but on a larger temporal scale they pay more attention to the particular objects involved. In spatial reasoning about small objects people tend to imagine objects being moved by an external force, but when reasoning about large environments they tend to imagine themselves moving within the environment. Thus, the computational form of cognitive operations appears to depend on the taxonomic, spatial, and temporal scale of the objects of those operations.