van Rooij, Robert and Katrin Schulz (2020). Generics and typicality: A bounded rationality approach. Linguistics and Philosophy 43, 83-117.
Traditionally, a category was defined in terms of a critical set of attributes the possession of which was taken to be both necessary and sufficient to be a member of the kind. But this traditional conception of categories is now largely abandoned. Typicality plays an important role in more recent theories of categorization and it will play a crucial role in our analysis of generic statements as well. One of the main claims of this paper is that a generic of the form ‘Gs are f ’ is true if f is a typical feature of Gs, or that typical members of the category G have feature f. Typicality is well studied in cognitive psychology. According to prototype theory, groups (or categories) are represented by typical members, rather than by all of them and only them, or by typical features, rather than by necessary and sufficient features, because agents have limited attention and limited recall of examples. But what are a group’s typical members or features? According to Rosch (1973), it is the central, or average members of the group, or the features most members have. Centrality is determined in terms of a notion of similarity, which is taken to be based, in one way or another on frequency and correlation information. Barsalou (1985) experimentally showed on the basis of a thorough correlational analysis, however, that at least for goal-derived artificial categories, the typical members are instead the category’s ideal members; those that best satisfy the goal. For example, the ideal of the category ‘things to eat on a diet’ presumably is ‘zero calories,’ which clearly is not a common, but rather an extreme value for members of the category. Idealness can be defined as the extent to which a certain object displays a quality that is directly related to the goal. More recent empirical findings (e.g. Lynch et al. 2000; Palmeri and Nosofsky 2001; Burnett et al. 2005; Ameel and Storms 2006) show that extreme members of a group are also considered typical for many, if not most, other types of categories, namely if categorization is performed in a contrastive way. Typical members of a category when defined contrastively have features that distinguish them from members of other categories; as such, they highlight, or exaggerate, real differences between groups (p. 93-94).