In this article we present two sets of experiments designed to investigate the acquisition of scalar implicatures. Scalar implicatures arise in examples like Some profissors are famous where the speaker's use of some typically indicates that s/he had reasons not to use a more informative term, e.g. all. Someprofissors are famous therefore gives rise to the implicature that not all professors are famous. Recent studies on the development of pragmatics suggest that preschool children are often insensitive to such implicatures when they interpret scalar terms (Noveck 2001 for terms like might and some; Chierchia, Crain, Guasti, Gualmini and Meroni 2001 for or). This conclusion raises two important questions: a) are all scalar terms treated in the same way by young children?, and b) does the child's difficulty reflect a genuine inability to derive scalar implicatures or is it due to demands imposed by the experimental task on an otherwise pragmatically savvy child? Experiment 1 addresses the first question by testing a group of 30 5-year-olds and 30 adults (all native speakers of Greek) on three different scales, meriki/ oli (some/all), dio/ tris (two/three) and arxi<o / teliono (start/finish). In each case, subjects were presented with contexts which satisfy the truth conditions of the stronger (i.e. more informative) terms on each scale (i.e. all, three and finish) but were described using the weaker terms of the scales (i.e. some, two, start). We found that while adults overwhelmingly rejected these infelicitous descriptions, children almost never did so. Children also differed from adults in that thei rejection rate on the numerical scale was reliably higher than on the two other scales. In order to address question (b), we trained a group of 30 5-year-olds to detect in...

The field of children's testimony is in turmoil, but a resolution to seemingly intractable debates now appears attainable. In this review, we place the current disagreement in historical context and describe psychological and legal views of child witnesses held by scholars since the turn of the 20th century. Although there has been consistent interest in children's suggestibility over the past century, the past 15 years have been the most active in terms of the number of published studies and novel theorizing about the causal mechanisms that underpin the observed findings. A synthesis of this research posits three &quot;families &quot; of factors—cognitive, social, and biological—that must be considered if one is to understand seemingly contradictory interpretations of the findings. We conclude that there are reliable age differences in suggestibility but that even very young children are capable of recalling much that is forensically relevant. Findings are discussed in terms of the role of expert witnesses. Since the turn of the century, psycholegal scholars have examined the suggestibility of children's testimony in an effort to determine whether they would be credible witnesses. A major issue in this research concerns the degree to which heightened

Flexible induction is the adaptation of probabilistic inferences to changing problems. Young children’s flexibility was tested in a word-learning task. Children 3 to 6 years old were told 3 novel words for each of several novel objects. Children generalized each word to other objects with the same body shape, the same material, or the same part as the first object. Each word was preceded by a different predicate (i.e., “looks like a …, ” “is made of …, ” or “has a …”) that implies a different attribute (shape, material, or part, respectively). Three-year-olds showed limited use of predicates to infer word meanings, and they used predicates from previous trials to infer the meanings of later words. 4- to 6-year-olds used predicate cues more consistently and made inferences that were implied by the most recent predicate cue. Notably, 3-year-olds performed near ceiling in a control task that eliminated the need to use probabilistic inductive cues (Experiment 3). The results suggest that flexibility develops as a function of (a) sensitivity to between-problem variability and indeterminacy and (b) ability to decontextualize the most recent verbal cue to guide of inductive inferences. The epitome of human reasoning is the ability to solve variable, novel problems while ignoring irrelevant information. This is difficult for adults (Dominowski,

To test preschoolers ’ ability to flexibly switch between abstract rules differing in difficulty, nintythree 3-, 4-, and 5-year-olds were instructed to switch from an (easier) shape-sorting to a (harder) function-sorting rule, or vice versa. Children learned one rule, sorted four test sets, then learned the other rule, and sorted four more sets. In a control condition, seventy-two 3–5-year-old children learned one rule and were re-trained on that rule before the second test block. Half of each group received metacognitive reminders to “think about ” the current rule before each test trial. The shape rule was easier: many 3-year-olds failed to follow the function rule, confirming findings of Deák et al. (2002). Switching rules did not reduce overall rule-following. However, reminders facilitated rule-following when rules were switched, but not when a rule was repeated (i.e., control condition). Reminders actually reduced rule-following by control children who got the easier (shape) rule. The results show (1) 4-year-olds readily switch between abstract rules, even if the second rule requires ignoring obvious, conflicting perceptual information (i.e., shape); (2) some rule-switching tasks do not impose performance costs on children, and (3) children’s rule-following consistency and flexibility depend on the nature of available social support. © 2004 Elsevier Inc. All rights reserved.