Generic sentences (e.g., bare plural sentences such as “dogs have four legs” and “mosquitoes carry malaria”) are used to talk about kinds of things. Three experiments investigated the conceptual foundations of generics as well as claims within the formal semantic approaches to generics concerning the roles of prevalence, cue validity and normalcy in licensing generics. Two classes of generic sentences that pose challenges to both the conceptually based and formal semantic approaches to generics were investigated. Striking property generics (e.g. “sharks (...) bite swimmers”) are true even though only a tiny minority of instances have the property and thus pose obvious problems for quantificational approaches, and they also do not seem to characterize kinds in terms of the principled or statistical connections investigated in previous research ( Prasada and Dillingham, 2006 ; Prasada and Dillingham, 2009). The second class — minority characteristic generics (e.g. “ducks lay eggs”) — also poses serious problems for quantificational accounts, and appears to involve principled connections even though fewer than half of its instances have the relevant property. The experiments revealed three principal discoveries: first, striking generics involve neither principled nor statistical connections. Instead, they involve a causal connection between a kind and a property. Second, minority characteristic generics exhibit the characteristics of principled connections, which suggests that principled connections license the expectation that most instances will have the property, but do not require it. Finally, the experiments also provided evidence that prevalence and the acceptability of generics may be dissociated and provided data that are problematic for normalcy approaches to generics, and for the idea that cue validity licenses low prevalence generics. As such, the studies provided evidence in favor of a conceptually based approach to the semantics of generics ( Leslie, 2007 ; Leslie, 2008; see also Carlson, 2009). (shrink)

Generic statements (e.g., “Birds lay eggs”) express generalizations about categories. In this paper, we hypothesized that there is a paradoxical asymmetry at the core of generic meaning, such that these sentences have extremely strong implications but require little evidence to be judged true. Four experiments confirmed the hypothesized asymmetry: Participants interpreted novel generics such as “Lorches have purple feathers” as referring to nearly all lorches, but they judged the same novel generics to be true given a wide range of prevalence (...) levels (e.g., even when only 10% or 30% of lorches had purple feathers). A second hypothesis, also confirmed by the results, was that novel generic sentences about dangerous or distinctive properties would be more acceptable than generic sentences that were similar but did not have these connotations. In addition to clarifying important aspects of generics’ meaning, these findings are applicable to a range of real-world processes such as stereotyping and political discourse. (shrink)

Generic generalizations such as ‘mosquitoes carry the West Nile virus’ or ‘sharks attack bathers’ are often accepted by speakers despite the fact that very few members of the kinds in question have the predicated property. Previous work suggests that such low-prevalence generalizations may be accepted when the properties in question are dangerous, harmful, or appalling. This paper argues that the study of such generic generalizations sheds light on a particular class of prejudiced social beliefs, and points to new ways in (...) which those beliefs might be undermined and combatted. (shrink)

Ducks lay eggs' is a true sentence, and `ducks are female' is a false one. Similarly, `mosquitoes carry the West Nile virus' is obviously true, whereas `mosquitoes don't carry the West Nile virus' is patently false. This is so despite the egg-laying ducks' being a subset of the female ones and despite the number of mosquitoes that don't carry the virus being ninety-nine times the number that do. Puzzling facts such as these have made generic sentences defy adequate semantic treatment. (...) However complex the truth conditions of generics appear to be, though, young children grasp generics more quickly and readily than seemingly simpler quantifiers such as `all' and `some'. I present an account of generics that not only illuminates the strange truth conditions of generics, but also explains how young children find them so comparatively easy to acquire. I then argue that generics give voice to our most cognitively primitive generalizations and that this hypothesis accounts for a variety of facts ranging from acquisition patterns to cross-linguistic data concerning the phonological articulation of operators. I go on to develop an account of the nature of these cognitively fundamental generalizations and argue that this account explains the strange truth-conditional behavior of generics. (shrink)

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)

Cimpian et al. observed that we accept generic statements of the form ‘Gs are f’ on relatively weak evidence, but that if we are unfamiliar with group G and we learn a generic statement about it, we still treat it inferentially in a much stronger way: all Gs are f. This paper makes use of notions like ‘representativeness’, ‘contingency’ and ‘relative difference’ from psychology to provide a uniform semantics of generics that explains why people accept generics based on weak evidence. (...) The spirit of the approach has much in common with Leslie’s cognition-based ideas about generics, but the semantics will be grounded on a strengthening of Cohen’s relative readings of generic sentences. In contrast to Leslie and Cohen, we propose a uniform semantic analysis of generics. The basic intuition is that a generic of the form ‘Gs are f’ is true because f is typical for G, which means that f is valuably associated with G. We will make use of Kahneman and Tversky’s Heuristics and Biases approach, according to which people tend to confuse questions about probability with questions about representativeness, to explain pragmatically why people treat many generic statements inferentially in a much stronger way. (shrink)

This paper explores the role of generics in social cognition. First, we explore the nature and effects of the most common form of generics about social kinds. Second, we discuss the nature and effects of a less common but equally important form of generics about social kinds. Finally, we consider the implications of this discussion for how we ought to use language about the social world.

Generic statements express generalizations about categories and present a unique semantic profile that is distinct from quantified statements. This paper reports two studies examining the development of children's intuitions about the semantics of generics and how they differ from statements quantified by all, most, and some. Results reveal that, like adults, preschoolers recognize that generics have flexible truth conditions and are capable of representing a wide range of prevalence levels; and interpret novel generics as having near-universal prevalence implications. Results further (...) show that by age 4, children are beginning to differentiate the meaning of generics and quantified statements; however, even 7- to 11-year-olds are not adultlike in their intuitions about the meaning of most-quantified statements. Overall, these studies suggest that by preschool, children interpret generics in much the same way that adults do; however, mastery of the semantics of quantified statements follows a more protracted course. (shrink)

Two experiments investigated whether 4- and 5-year-old children are sensitive to whether the content of a generalization is about a salient or noteworthy property (henceforth “striking”) and whether varying the number of exceptions has any effect on children’s willingness to extend a property after having heard a generalization. Moreover, they investigated how the content of a generalization interacts with exception tolerance. Adult data were collected for comparison. We used generalizations to describe novel kinds (e.g., “glippets”) that had either a neutral (...) (e.g., “play with toys”) or a striking property (e.g., “play with fire”) and measured how willing participants were to extend the property to a new instance of the novel kind. Experiment 1 demonstrated that both adults and children show sensitivity to strikingness in that striking properties were extended less than neutral ones, although children extended less than adults overall. The responses of both age groups were significantly different from chance. Experiment 2 introduced varying numbers of exceptions to the generalization made (minimal: 1 exception; maximal: 3 exceptions). Both adults and children extended both types of properties even in the face of exceptions, but to a lower degree than in Experiment 1. Striking properties were extended less than neutral ones, as in Experiment 1. We observed that the greater the number of exceptions, the lower the rates of extension we obtained, for both types of properties in adults, but only with striking properties in children. Children seemed to keep track of varying numbers of exceptions for striking properties, but their performance did not differ from chance. The findings underscore that 4- and 5-year-old children are sensitive to strikingness and to exception tolerance for generalizations and are developing toward an adult-like behavior with respect to the interplay between strikingness and exception tolerance when they learn about novel kinds. We discuss the implications of these results with regards to how children make generalizations. (shrink)

Much evidence suggests that, from a young age, humans are able to generalize information learned about a subset of a category to the category itself. Here, we propose that—beyond simply being able to perform such generalizations—people are biased to generalize to categories, such that they routinely make spontaneous, implicit category generalizations from information that licenses such generalizations. To demonstrate the existence of this bias, we asked participants to perform a task in which category generalizations would distract from the main goal (...) of the task, leading to a characteristic pattern of errors. Specifically, participants were asked to memorize two types of novel facts: quantified facts about sets of kind members and generic facts about entire kinds. Moreover, half of the facts concerned properties that are typically generalizable to an animal kind, and half concerned properties that are typically more idiosyncratic. We predicted that—because of the hypothesized bias—participants would spontaneously generalize the quantified facts to the corresponding kinds, and would do so more frequently for the facts about generalizable properties. In turn, these generalizations would lead to a higher rate of quantified-to-generic memory errors for the generalizable properties. The results of four experiments supported this prediction. Moreover, the same generalizable-versus-idiosyncratic difference in memory errors occurred even under cognitive load, which suggests that the hypothesized bias operates unnoticed in the background, requiring few cognitive resources. In sum, this evidence suggests the presence of a powerful bias to draw generalizations about kinds. (shrink)