Children's ability to infer utterance veracity from speaker informedness

How children revise their beliefs in light of reasons

We investigate how the ability to respond appropriately to reasons provided in discourse develops in young children. In Study 1 (N = 58, Germany, 26 girls), 4- and 5-, but not 3-year-old children, differentiated good from bad reasons. In Study 2 (N = 131, Germany, 64 girls), 4- and 5-year-old children considered both the strength of evidence for their initial belief and the quality of socially provided reasons for an alternative view when deciding whether to change their minds. Study 3 (N = 80, the United States, 42 girls, preregistered) shows that 4- and 5-year-old children also consider meta-reasons (reasons about reasons) in their belief revision. These results suggest that by age 4, children possess key critical thinking capacities for participating in public discourse.

Preschool children's use of meta-talk to make rational collaborative decisions

In collaborative decision-making, partners compare reasons behind conflicting proposals through meta-talk. We investigated UK-based preschoolers' (mixed socioeconomic status) use of meta-talk (Data collection: 2018-2020). In Study 1, 5- and 7-year-old peer dyads (N = 128, 61 girls) heard conflicting claims about an animal from two informants. One prefaced her claim with "I know"; the other with "I think". Dyads identified the more reliable informant through meta-talk ("She said she knows"). In Study 2, 3- and 5-year-olds (N = 64, 34 girls) searched for a toy with an adult partner making incorrect proposals. Children refuted this through reporting what they had witnessed (It cannot be there because "I saw it move", "she moved it"). In preschool period, children start using meta-talk to make rational collaborative decisions.

Self-derivation through memory integration: A model for accumulation of semantic knowledge

Semantic knowledge accumulates through explicit means and productive processes (e.g., analogy). These means work in concert when information explicitly acquired in separate episodes is integrated, and the integrated representation is used to self-derive new knowledge. We tested whether (a) self-derivation through memory integration extends beyond general information to science content, (b) self-derived information is retained, and (c) details of explicit learning episodes are retained. Testing was in second-grade classrooms (children 7-9 years). Children self-derived new knowledge; performance did not differ for general knowledge (Experiment 1) and science curriculum facts (Experiment 2). In Experiment 1, children retained self-derived knowledge over one week. In Experiment 2, children remembered details of the learning episodes that gave rise to self-derived knowledge; performance suggests that memory integration is dependent on explicit prompts. The findings support nomination of self-derivation through memory integration as a model for accumulation of semantic knowledge and inform the processes involved.

Trait or testimony? Children's preferences for positive informants

Research indicates that children often show a positivity bias, or a tendency to favor positive information over negative information, in assessments of informant credibility in social and nonsocial situations. The current study investigated whether young children prioritize positive informant traits (i.e., nice vs. mean informant) as compared with positive speech content (i.e., positive vs. negative evaluation) in conflicting assessments of a work product. A total of 123 4- to 8-year-olds heard stories about a nice informant who gave a negative evaluation of a painting and a mean informant who gave a positive evaluation of the painting. Participants were asked who they would endorse, who they would ask about a future painting, and their friendship preferences. Children endorsed and asked the mean informant who provided positive testimony, but they chose to befriend the nice informant who provided negative testimony. Endorsements of positive testimony increased with age. Findings are considered in the context of the broader literature on selective social learning and trait understanding.

How Gullible are We? A Review of the Evidence from Psychology and Social Science

A long tradition of scholarship, from ancient Greece to Marxism or some contemporary social psychology, portrays humans as strongly gullible—wont to accept harmful messages by being unduly deferent. However, if humans are reasonably well adapted, they should not be strongly gullible: they should be vigilant toward communicated information. Evidence from experimental psychology reveals that humans are equipped with well-functioning mechanisms of epistemic vigilance. They check the plausibility of messages against their background beliefs, calibrate their trust as a function of the source's competence and benevolence, and critically evaluate arguments offered to them. Even if humans are equipped with well-functioning mechanisms of epistemic vigilance, an adaptive lag might render them gullible in the face of new challenges, from clever marketing to omnipresent propaganda. I review evidence from different cultural domains often taken as proof of strong gullibility: religion, demagoguery, propaganda, political campaigns, advertising, erroneous medical beliefs, and rumors. Converging evidence reveals that communication is much less influential than often believed—that religious proselytizing, propaganda, advertising, and so forth are generally not very effective at changing people's minds. Beliefs that lead to costly behavior are even less likely to be accepted. Finally, it is also argued that most cases of acceptance of misguided communicated information do not stem from undue deference, but from a fit between the communicated information and the audience's preexisting beliefs.

The Influence of First-Hand Testimony and Hearsay on Children's Belief in the Improbable

Children (3.5-8.5 years; n = 105) heard claims about the occurrence of improbable or impossible events, then were asked whether the events could really happen. Some claims were based on informants' first-hand observations and others were hearsay. A baseline group (n = 56) reported their beliefs about these events without hearing testimony. Neither first-hand claims nor hearsay influenced beliefs about impossible events, which remained low across the age range. Hearsay (but not first-hand claims) did influence beliefs about improbable events. Preschoolers expressed greater belief following hearsay, compared to their beliefs following first-hand claims and compared to the baseline group's beliefs. By contrast, older children expressed less belief following hearsay, compared to their beliefs following first-hand claims and compared to the baseline group's beliefs.

Perspectives on Perspective Taking: How Children Think About the Minds of Others

Perspective taking, or "theory of mind," involves reasoning about the mental states of others (e.g., their intentions, desires, knowledge, beliefs) and is called upon in virtually every aspect of human interaction. Our goals in writing this chapter were to provide an overview of (a) the research questions developmental psychologists ask to shed light on how children think about the inner workings of the mind, and (b) why such research is invaluable in understanding human nature and our ability to interact with, and learn from, one another. We begin with a brief review of early research in this field that culminated in the so-called litmus test for a theory of mind (i.e., false-belief tasks). Next, we describe research with infants and young children that created a puzzle for many researchers, and briefly mention an intriguing approach researchers have used to attempt to "solve" this puzzle. We then turn to research examining children's understanding of a much broader range of mental states (beyond false beliefs). We briefly discuss the value of studying individual differences by highlighting their important implications for social well-being and ways to improve perspective taking. Next, we review work illustrating the value of capitalizing on children's proclivity for selective social learning to reveal their understanding of others' mental states. We close by highlighting one line of research that we believe will be an especially fruitful avenue for future research and serves to emphasize the complex interplay between our perspective-taking abilities and other cognitive processes.

Young Children's Reliance on Information From Inaccurate Informants

Prior work shows that children selectively learn from credible speakers. Yet little is known how they treat information from non-credible speakers. This research examined to what extent and under what conditions children may or may not learn from problematic sources. In three studies, we found that children displayed trust toward previously inaccurate speakers. Children were equally likely to extend labels from previously accurate and inaccurate speakers to novel objects. Moreover, they expected third parties to share labels provided by previously inaccurate speakers. Only when there was clear evidence that the speakers' information was wrong (as in the case when speakers' perceptual access to the information was blocked), did young children reject the label. Together, the findings provide evidence that young children do not completely ignore the labels supplied by non-credible speakers unless there is strong reason to do so.

Visual access trumps gender in 3- and 4-year-old children's endorsement of testimony

Several studies have investigated how preschoolers weigh social cues against epistemic cues when taking testimony into account. For instance, one study showed that 4- and 5-year-olds preferred to endorse the testimony of an informant who had the same gender as the children; by contrast, when the gender cue conflicted with an epistemic cue--past reliability--the latter trumped the former. None of the previous studies, however, has shown that 3-year-olds can prioritize an epistemic cue over a social cue. In Experiment 1, we offer the first demonstration that 3-year-olds favor testimony from a same-gender informant in the absence of other cues. In Experiments 2 and 3, an epistemic cue-visual access--was introduced. In those experiments, 3- and 4-year-olds endorsed the testimony of the informant with visual access regardless of whether it was a same-gender informant (Experiment 3) or a different-gender informant (Experiment 2). These results demonstrate that 3-year-olds are able to give more weight to an epistemic cue than to a social cue when evaluating testimony.

Reasoning About Trust Among Individuals With Williams Syndrome

The present study examines whether individuals with Williams syndrome (WS) might indiscriminately trust in others, as is suggested by their strong tendency to approach and interact with strangers. To assess this possibility, adults with WS (N=22) and typical development (N=25) were asked to reason about the trustworthiness of people who lie to avoid getting in trouble versus to avoid hurting others' feelings. Findings indicated that participants with WS distrusted both types of liars and made little distinction between them. These results suggest that the high level of social approach behavior in individuals with WS cannot be explained in terms of indiscriminate trust.

Children's Understanding of Behavioral Consequences of Epistemic States: A Comparison of Knowledge, Ignorance, and False Belief

The author addressed the issue of the simultaneity of false belief and knowledge understanding by investigating children's ability to predict the behavioral consequences of knowledge, ignorance, and false belief. The second aim of the study was to explore the role of counterfactuals in knowledge understanding. Ninety-nine (99) children, age 3-7 years old, completed the unexpected transfer task and a newly designed task in which a protagonist experienced 1 of the following 4 situations: knowing a fact, not knowing a fact, knowing a procedure, and not knowing a procedure. The results showed that factual ignorance was as difficult as false belief for the children, whereas the other conditions were all easier than false belief, suggesting that the well-known lag between ignorance and false belief may be partly methodologically based. The results provide support for a common underlying conceptual system for both knowing and believing, and evidence of the role of counterfactual reasoning in the development of epistemic state understanding. Methodological variations of the new task are proposed for future research.

Confronting, Representing, and Believing Counterintuitive Concepts: Navigating the Natural and the Supernatural

Recent research shows that even preschoolers are skeptical; they frequently reject claims from other people when the claims conflict with their own perceptions and concepts. Yet, despite their skepticism, both children and adults come to believe in a variety of phenomena that defy their first-hand perceptions and intuitive conceptions of the world. In this review, we explore how children and adults acquire such concepts. We describe how a similar developmental process underlies mental representation of both the natural and the supernatural world, and we detail this process for two prominent supernatural counterintuitive ideas-God and the afterlife. In doing so, we highlight the fact that conceptual development does not always move in the direction of greater empirical truth, as described within naturalistic domains. We consider factors that likely help overcome skepticism and, in doing so, promote belief in counterintuitive phenomena. These factors include qualities of the learners, aspects of the context, qualities of the informants, and qualities of the information.

Developing expectations regarding the boundaries of expertise

Three experiments examined elementary school-aged children's and adults' expectations regarding what specialists (i.e., those with narrow domains of expertise) and generalists (i.e., those with broad domains of expertise) are likely to know. Experiment 1 demonstrated developmental differences in the ability to differentiate between generalists and specialists, with younger children believing generalists have more specific trivia knowledge than older children and adults believed. Experiment 2 demonstrated that children and adults expected generalists to have more underlying principles knowledge than specific trivia knowledge about unfamiliar animals. However, they believed that generalists would have more of both types of knowledge than themselves. Finally, Experiment 3 demonstrated that children and adults recognized that underlying principles knowledge can be generalized between topics closely related to the specialists' domains of expertise. However, they did not recognize when this knowledge was generalizable to topics slightly less related, expecting generalists to know only as much as they would. Importantly, this work contributes to the literature by showing how much of and what kinds of knowledge different types of experts are expected to have. In sum, this work provides insight into some of the ways children's notions of expertise change over development. The current research demonstrates that between the ages of 5 and 10, children are developing the ability to recognize how experts' knowledge is likely to be limited. That said, even older children at times struggle to determine the breadth of an experts' knowledge.

Do children learn from pretense?

Pretend play presents an interesting puzzle. Children generally must keep pretense separate from reality or else pretend would confuse their real-world representations. Children spend a great deal of time pretending, and so failing to take any information from pretend scenarios would present a lost opportunity; however, little research has investigated whether it is possible or efficient for children to learn new information they encounter during pretend play. In two tightly controlled studies using blind testers, we taught children information of two types (labels and object functions) in a pretend or real context. Children learned the novel functions in the pretend condition, and they inferred that the novel object would be similar in appearance to the substitute used to represent it during pretense. These findings coincide with other recent work suggesting that children can learn new information in pretense contexts that they can then apply to the real world, although this learning may differ in important ways from learning in real contexts.

Young children's use of honesty as a basis for selective trust

The ability of 3- to 5-year-old children to reason about trust in relation to the honest behavior of others was examined across five studies (total N=496). Results showed that although 4-year-olds differentiated between honest and dishonest sources in their trust judgments, only 5-year-olds demonstrated a clear capacity to differentiate between honesty and a trust-irrelevant dimension (i.e., cleanliness) in these trust judgments. This was seen in their tendency to trust honest characters more than clean ones and to distrust dishonest characters more than unclean ones. This was also seen in their tendency to choose honest unclean characters over dishonest clean ones in their trust judgments. Results suggest that children use honesty as a basis for selective trust even before they appreciate which specific traits are relevant to trust.

When do children trust the expert? Benevolence information influences children's trust more than expertise

How do children use informant niceness, meanness, and expertise when choosing between informant claims and crediting informants with knowledge? In Experiment 1, preschoolers met two experts providing conflicting claims for which only one had relevant expertise. Five-year-olds endorsed the relevant expert's claim and credited him with knowledge more often than 3-year-olds. In Experiment 2, niceness/meanness information was added. Although children most strongly preferred the nice relevant expert, the children often chose the nice irrelevant expert when the relevant one was mean. In Experiment 3, a mean expert was paired with a nice non-expert. Although this nice informant had no expertise, preschoolers continued to endorse his claims and credit him with knowledge. Also noteworthy, children in all three experiments seemed to struggle more to choose the relevant expert's claim than to credit him with knowledge. Together, these experiments demonstrate that niceness/meanness information can powerfully influence how children evaluate informants.

Children's use of communicative intent in the selection of cooperative partners

Within the animal kingdom, human cooperation represents an outlier. As such, there has been great interest across a number of fields in identifying the factors that support the complex and flexible variety of cooperation that is uniquely human. The ability to identify and preferentially interact with better social partners (partner choice) is proposed to be a major factor in maintaining costly cooperation between individuals. Here we show that the ability to engage in flexible and effective partner choice behavior can be traced back to early childhood. Specifically, across two studies, we demonstrate that by 3 years of age, children identify effective communication as "helpful" (Experiments 1 & 2), reward good communicators with information (Experiment 1), and selectively reciprocate communication with diverse cooperative acts (Experiment 2). Taken together, these results suggest that even in early childhood, humans take advantage of cooperative benefits, while mitigating free-rider risks, through appropriate partner choice behavior.

Knowing when to doubt: developing a critical stance when learning from others

Children may be biased toward accepting information as true, but the fact remains that children are exposed to misinformation from many sources, and mastering the intricacies of doubt is necessary. The current article examines this issue, focusing on understanding developmental changes and consistencies in children's ability to take a critical stance toward information. Research reviewed includes studies of children's ability to detect ignorance, inaccuracy, incompetence, deception, and distortion. Particular emphasis is placed on what this research indicates about how children are reasoning about when to trust and when to doubt. The remainder of the article proposes a framework to evaluate preexisting research and encourage further research, closing with a discussion of several other overarching questions that should be considered to develop a model to explain developmental, individual, and situational differences in children's ability to evaluate information.

Informants' traits weigh heavily in young children's trust in testimony and in their epistemic inferences

This study examined how informants' traits affect how children seek information, trust testimony, and make inferences about informants' knowledge. Eighty-one 3- to 6-year-olds and 26 adults completed tasks where they requested and endorsed information provided by one of two informants with conflicting traits (e.g., honesty vs. dishonesty). Participants also completed tasks where they simultaneously considered informants' traits and visual access to information when inferring their knowledge and trusting their testimony. Children and adults preferred to ask and endorse information provided by people who are nice, smart, and honest. Moreover, these traits influenced the knowledge that young children attributed to informants. Children younger than 5 years of age reported that people with positive traits were knowledgeable even when they lacked access to relevant information.

Take it as read: origins of trust in knowledge gained from print

The ability to read opens up the possibility of learning about the world indirectly via print sources, providing a powerful new opportunity for children who have for years learned effectively from what people tell them. We compared children's trust in printed versus oral information. We also examined whether children who showed preferential trust in an informant with print assumed that the informant was still reliable about new information offered without print support. Children (N=89 aged 3-6 years) received conflicting suggestions from two dolls about which picture showed an unfamiliar target. Only one doll's suggestion referred to a printed label read aloud. Prereaders, despite their exposure to print and presumed experience of others treating print sources as authoritative, showed no clear evidence of preferential trust in the suggestions with print support. Early readers, in contrast, consistently preferred the suggestions with print support. Importantly, despite having treated the doll with print as having a history of accuracy, early readers no longer showed trust in that doll when it subsequently had no print support. Children at the very earliest stages of reading treated the doll with print appropriately as having gained only specific information from the print sources.

Gaining knowledge via other minds: children's flexible trust in others as sources of information

In five experiments, we examined 3- to 6-year-olds' understanding that they could gain knowledge indirectly from someone who had seen something they had not. Consistent with previous research, children judged that an informant, who had seen inside a box, knew its contents. Similarly, when an informant marked a picture to indicate her suggestion as to the content of the box, 3- to 4-year-olds trusted this more frequently when the informant had seen inside the box than when she had not. Going beyond previous research, 3- to 4-year-olds were also sensitive to informants' relevant experience when they had to look over a barrier to see the marked picture, or ask for the barrier to be raised. Yet when children had to elicit the informant's suggestion, rather than just consult a suggestion already present, even 4- to 5-year-olds were no more likely to do so when the informant had seen the box's content than when she had not, and no more likely to trust the well-informed suggestion than the uninformed one. We conclude that young children who can ask questions may not yet fully understand the process by which they can gain accurate information from someone who has the experience they lack.

The development of distrust

Preschool-age children's reasoning about the reliability of deceptive sources was investigated. Ninety 3- to 5-year-olds watched several trials in which an informant gave advice about the location of a hidden sticker. Informants were either helpers who were happy to give correct advice, or trickers who were happy to give incorrect advice. Three-year-olds tended to accept all advice from both helpers and trickers. Four-year-olds were more skeptical but showed no preference for advice from helpers over trickers, even though they differentiated between helpers and trickers on metacognitive measures. Five-year-olds systematically preferred advice from helpers. Selective trust was associated with children's ability to make mental state inferences.

Believing what you're told: young children's trust in unexpected testimony about the physical world

How do children resolve conflicts between a self-generated belief and what they are told? Four studies investigated the circumstances under which toddlers would trust testimony that conflicted with their expectations about the physical world. Thirty-month-olds believed testimony that conflicted with a naive bias (Study 1), and they also repeatedly trusted testimony that conflicted with an event they had just seen (Study 2)-even when they had an incentive to ignore the testimony (Study 3). Children responded more skeptically if they could see that the testimony was wrong as it was being delivered (Study 3), or if they had the opportunity to accumulate evidence confirming their initial belief before hearing someone contradict it (Study 4). Together, these studies demonstrate that toddlers have a robust bias to trust even surprising testimony, but this trust can be influenced by how much confidence they have in their initial belief.

Dealing with conflicting information: young children's reliance on what they see versus what they are told

Children often learn about the world through direct observation. However, much of children's knowledge is acquired through the testimony of others. This research investigates how preschoolers weigh these two sources of information when they are in conflict. Children watched as an adult hid a toy in one location. Then the adult told children that the toy was in a different location (i.e. false testimony). When retrieving the toy, 4- and 5-year-olds relied on what they had seen and disregarded the adult's false testimony. However, most 3-year-olds deferred to the false testimony, despite what they had directly observed. Importantly, with a positive searching experience based on what they saw, or with a single prior experience with an adult as unreliable, 3-year-olds subsequently relied on their first-hand observation and disregarded the adult's false testimony. Thus, young children may initially be credulous toward others' false testimony that contradicts their direct observation, but skepticism can develop quickly through experience.

Show or tell: testimony is sufficient to induce the curse of knowledge in three- and four-year-olds

Because much of what children learn extends beyond their first-hand experience, they are reliant upon the testimony of others to acquire information about aspects of the world they have not experienced directly. Here we asked whether testimony alone would be sufficient to induce cognitive biases in knowledge attribution that have been observed when children acquire information through direct observation. A total of 80 three- and four-year-old children were tested on a "curse of knowledge" task to assess their inability to override their own knowledge when asked to assess the knowledge of a nave other. In the present study, we tested children's ability to override knowledge gained through testimony rather than knowledge gained through visual experience. Testimony alone was sufficient to induce the curse of knowledge in three- and four-year-olds. Knowledge obtained through the testimony of others is apparently subject to some of the same cognitive biases that are present when children learn through observation.

Commentary: what we can learn from research on evidentials

Young children's well-documented difficulty reporting the sources of their knowledge, and their susceptibility to misleading suggestions about what they saw for themselves, might be reduced when their linguistic community expresses knowledge sources with grammatical evidential markers. Alternatively, until children have acquired certain cognitive prerequisites, they may interpret evidentials simply as markers of speakers' certainty. There is evidence supportive of both views, but with more precisely formulated research questions, specially tailored tasks, and more cross-linguistic comparisons, we can come to understand better the developmental intertwining of linguistic, metalinguistic, and cognitive aspects of children's handling of sources of knowledge.

The role of evidentiality in Bulgarian children's reliability judgments

Evidentials are grammatical source-of-knowledge markers. In Bulgarian they provide information about authorship--whether the speaker has personally acquired the information or not--and modality--whether perceptual or cognitive mechanisms were involved in the information's generation. In two experiments, Bulgarian kindergarteners and third-graders (ages 6 and 9, N=96) had to decide which one of two utterances containing different evidentials to believe. Experiment 1 showed that children draw on modality information in their decisions: Third-graders favored perceptual over cognitive and kindergartners cognitive over perceptual sources. Experiment 2 showed that third-graders can also draw on the authorship information carried by evidentials: they favored first- over second-hand information. The discussion focuses on understanding the development of children's use of evidentials.

Children's Critical Thinking When Learning From Others

A key component of critical thinking is the ability to evaluate the statements of other people. Because information that is obtained from others is not always accurate, it is important that children learn to reason about it critically. By as early as age 3, children understand that people sometimes communicate inaccurate information and that some individuals are more reliable sources than others. However, in many contexts, even older children fail to evaluate sources critically. Recent research points to the role of social experience in explaining why children often fail to engage in critical reasoning.

Limitations on reliability: regularity rules in the English plural and past tense

Two studies investigated 3- to 5-year-olds' trust in a reliable informant when judging novel labels and novel plural and past tense forms. In Study 1, children (N = 24) endorsed the names of new objects given by an informant who had earlier labeled familiar objects correctly over the names given by an informant who had labeled the same objects incorrectly. In Study 2, children (N = 24) endorsed novel names given by an informant who had earlier expressed the plural of familiar nouns correctly over one who had expressed the plural incorrectly. But children overwhelmingly endorsed the regular plural and past tense forms of new words provided by the formerly unreliable labeler (Study 1) or morphologist (Study 2) rather than irregular forms of those words provided by the formerly reliable informant.

Reasoning about the disclosure of success and failure to friends among children in the United States and China

Children's reasoning about individuals' willingness to disclose their successes and failures was investigated among 194 6- to 11-year-olds in the United States and China. In Study 1, participants showed a valence-matching effect, in which they predicted that individuals would be more likely to disclose their performance to an audience of friends if the friends' level of achievement was similar rather than dissimilar. This effect was weaker among children from China, who were more likely to justify their responses with reference to the implications for learning together or improving future performance. Results of Study 2 suggest that for children from the United States, the disclosure of successful performance to a friend who has performed poorly is seen as implicitly conveying the message "I'm better than you," whereas for children from China the message is "I can help you to do better." Results are interpreted with reference to cultural values and expectations about helping others to learn.

Mixing memories: the effects of rumors that conflict with children's experiences

This study examined age differences in children's vulnerability to be misled by two types of false overheard rumors, namely a rumor that suggested a reasonable explanation for an earlier unresolved experience and a rumor that suggested an explanation that conflicted with information already in memory. Results indicated that all of the children were highly susceptible to wrongly report the rumor as an actual experience when it merely filled a gap in memory. However, the 5- and 6-year-olds were better able than the 3- and 4-year-olds to resist the rumor when it suggested a conflicting explanation for a past event. Developmental changes in children's understanding of conflicting mental representations were linked to their ability to resist being misled by the conflicting rumor.

Evidentiality in language and cognition

What is the relation between language and thought? Specifically, how do linguistic and conceptual representations make contact during language learning? This paper addresses these questions by investigating the acquisition of evidentiality (the linguistic encoding of information source) and its relation to children's evidential reasoning. Previous studies have hypothesized that the acquisition of evidentiality is complicated by the subtleness and abstractness of the underlying concepts; other studies have suggested that learning a language which systematically (e.g. grammatically) marks evidential categories might serve as a pacesetter for early reasoning about sources of information. We conducted experimental studies with children learning Korean (a language with evidential morphology) and English (a language without grammaticalized evidentiality) in order to test these hypotheses. Our experiments compared 3- and 4-year-old Korean children's knowledge of the semantics and discourse functions of evidential morphemes to their (non-linguistic) ability to recognize and report different types of evidential sources. They also compared Korean children's source monitoring abilities to the source monitoring abilities of English-speaking children of the same age. We found that Korean-speaking children have considerable success in producing evidential morphology but their comprehension of such morphology is very fragile. Nevertheless, young Korean speakers are able to reason successfully about sources of information in non-linguistic tasks; furthermore, their performance in these tasks is similar to that of English-speaking peers. These results support the conclusion that the acquisition of evidential expressions poses considerable problems for learners; however, these problems are not (necessarily) conceptual in nature. Our data also suggest that, contrary to relativistic expectations, children's ability to reason about sources of information proceeds along similar lines in diverse language-learning populations and is not tied to the acquisition of the linguistic markers of evidentiality in the exposure language. We discuss implications of our findings for the relationship between linguistic and conceptual representations during development.

Children's Evaluation of Sources of Information About Traits

Children's assessment of the value of different sources of information about psychological traits was investigated among 6- to 7-year-olds and 10- to 11-year-olds across 5 studies (N = 330). Older children were more likely than younger children to reject self-report as a source of information about the highly evaluative traits smart and honest, but no such age-related difference was seen for the less evaluative comparison traits outgoing and nervous. A similar pattern of age-related differences was seen when children were asked to identify which of 4 sources of information--self-report, teacher report, peer report, or direct observation--would be most useful for obtaining information about the evaluative and comparison traits. The age-related increase in skepticism about self-report as a source of information for evaluative traits was associated with an increased appreciation of the role that social desirability plays in self-presentational processes.

Judging who knows best about yourself: developmental change in citing the self across middle childhood

Rosenberg (1979) reported that children under the age of 11 do not recognize that they are the authority on their own self-knowledge, placing authority instead with adults. However, results from Studies 1 and 2, in which 86 and 47 children, respectively, from predominantly White low- to middle-income communities participated, suggest that the shift from reliance on adults to self occurs between the ages of 5 and 10 years. The studies also demonstrate parallel development in judging own and other people's self-knowledge. Study 3, in which 96 children from predominantly White low- to middle-income communities participated, shows the beginnings of sophisticated understanding in children aged 5 to 7 years, who differentiate between information about the self that is best judged by the self and information that can be judged by others. Suggestions are made as to why this aspect of understanding minds develops later than other aspects of psychological understanding.

Children's suggestibility in relation to their understanding about sources of knowledge

In the experiments reported here, children chose either to maintain their initial belief about an object's identity or to accept the experimenter's contradicting suggestion. Both 3- to 4-year-olds and 4- to 5-year-olds were good at accepting the suggestion only when the experimenter was better informed than they were (implicit source monitoring). They were less accurate at recalling both their own and the experimenter's information access (explicit recall of experience), though they performed well above chance. Children were least accurate at reporting whether their final belief was based on what they were told or on what they experienced directly (explicit source monitoring). Contrasting results emerged when children decided between contradictory suggestions from two differentially informed adults: Three- to 4-year-olds were more accurate at reporting the knowledge source of the adult they believed than at deciding which suggestion was reliable. Decision making in this observation task may require reflective understanding akin to that required for explicit source judgments when the child participates in the task.

Children's ability to make tentative interpretations of ambiguous messages

Consistent with prior research, 5- and 6-year-old children overestimated their knowledge of the intended referent of ambiguous messages. Yet they correctly revised their interpretations of ambiguous messages in light of contradicting information that followed immediately, while maintaining their initial interpretations of unambiguous messages (Experiment 1). Children of this age were able to integrate information over two successive ambiguous messages to identify the intended referent (Experiment 2). However, unlike 7- and 8-year-olds, they were no more likely to search for further information following ambiguous messages compared with unambiguous ones (Experiment 3). We conclude that although 5- and 6-year-olds' interpretations of ambiguous messages are not tentative at the outset, they can use source monitoring skills to treat them as tentative retrospectively, at least over short time spans.