Preschool Children Rarely Seek Empirical Data That Could Help Them Complete a Task When Observation and Testimony Conflict

Children learn about the world in a variety of ways. They can learn by paying attention to what other people do (Hoehl et al., 2019). They can learn from testimony directed toward themselves or toward other people (for reviews: Harris, Koenig, Corriveau, & Jaswal, 2018; Mills, 2013; Sobel & Kushnir, 2013; Tong, Wang, & Danovitch, 2020). And, they can gather evidence through exploration (Bonawitz et al., 2011; Schulz & Bonawitz, 2007; Yu, Landrum, Bonawitz, & Shafto, 2018), experimentation (Cook, Goodman, & Schulz, 2011; Köksal-Tuncer & Sodian, 2018), and question-asking (Callanan & Oakes, 1992; Kurkul & Corriveau, 2017). Children’s ability to learn from these diverse sources of information is one reason they are able to learn so much so quickly. Each of these sources of information can provide children with unique insights about the world. For example, by listening to other people, children can avoid costly mistakes and learn about unobservable scientific and religious phenomena they could not discover on their own (Harris & Koenig, 2006). By tracking statistical regularities young children can quickly build up and revise their understanding of causal structures without relying on other people’s testimony (Bridgers, Buchsbaum, Seiver, Griffiths, & Gopnik, 2016).

In addition to providing distinctive insights about the world, the testimony children receive and their firsthand experiences can also propel or challenge children’s learning, depending on whether these two sources provide consistent or inconsistent data about the same phenomena. When testimony and firsthand experience provides consistent data, children’s learning is strengthened because they have multiple sources confirming a given piece of information. However, when firsthand exploration and testimony conflict, children have to decide how to integrate these two sources of information, that is, whether either source should be considered more true or reliable than the other, whether both sources could possibly be true, or whether additional information is needed to resolve the conflict. Prior research has demonstrated that by 4 years of age, children can resolve conflicts between different sources of information (observation vs. testimony) based on the relative merits of each information source, for example, the strength of the observed evidence (probabilistic vs. deterministic) and the prior accuracy of an informant (Bridgers et al., 2016). This ability to appropriately weigh conflicting data allows children to quickly resolve the tension between conflicting sources when there is a clear discrepancy in their reliability. However, how do children react when different information sources are equally compelling and resolving that tension would help them complete a task? Do they gather additional information or attempt the task without it? Below, we review prior research pertinent to this central question.

Whether children are learning from what other people tell them or by tracking statistical regularities through observation, children are sensitive to the strength of the evidence that those two sources of information provide. When learning from other people, children assess informants based on a number of different cues and will reject testimony when they have reason to believe that an informant’s information is unreliable (for reviews: Harris et al., 2018; Mills, 2013; Sobel & Kushnir, 2013; Tong et al., 2020). For example, 4-year-old children keep track of whether an informant provided them with correct or incorrect information and adjust their trust in that informant as they interact with them and gain new information about their accuracy (Ronfard & Lane, 2018, 2019). Children also place more weight on observed data when this is generated by a knowledgeable rather than a naïve adult (Bonawitz et al., 2011; Butler & Markman, 2012; Kushnir, Wellman, & Gelman, 2008). Furthermore, when making inferences based on observed statistical patterns, 4-year-old children distinguish between deterministic and probabilistic patterns (Bridgers et al., 2016).

These prior studies demonstrate that children are able to appropriately weigh testimonial and observational evidence when these two sources of information are presented individually. However, how do children respond when both sources are available and conflict with each other? For example, how do they respond when what they are told about how a toy works conflicts with what they see? To find out, Bridgers et al. (2016) had an informant introduce 4- and 5-year-old children to a novel toy. This informant was introduced as either naïve or knowledgeable. Following the informant’s testimony about which block made the machine go, children observed data conflicting with the informant’s testimony. These data were either deterministic (the endorsed block activated the machine 0/6 times, whereas the unendorsed block activated it 6/6 times) or probabilistic (the endorsed block activated the machine 2/6 times, whereas the unendorsed block activated it 4/6 times). When subsequently asked which block made the machine go, children appropriately discarded the testimony from both the naïve and knowledgeable experimenter when they observed data clearly contradicting their testimony (i.e., the deterministic data). However, when they observed less conclusive data (i.e., the probabilistic data), their inferences differed based on the reliability of the experimenter. In such cases, children relied on what they saw when taught by the naïve experimenter, but did not show a preference for what they saw when taught by the knowledgeable experimenter.

In real-world situations, it is rare that children observe six identical and consecutive observations either confirming or conflicting with a claim. Rather, children might be told one thing, and then observe an event providing conflicting information. In such situations, the two sources are likely to be equally compelling, and the conflict between them can only be resolved by obtaining additional information. Thus, this study builds on prior results by asking how children respond when what they are told and what they observe conflict rather than converge and they have no reason to doubt either source of information. More specifically, we ask if children spontaneously seek out additional empirical information to resolve the conflict when given the opportunity to do so. To motivate children to seek out such information, we asked them to engage in a sorting task in which accurate sorting would benefit from the seeking of further information.

Prior research has shown that preschoolers engage in the exploratory investigation when causal information is confounded, for example, when it remains unclear whether either or both levers activate a toy (Schulz & Bonawitz, 2007). Accordingly, we might expect that preschoolers will also engage in the exploratory investigation when facing conflicting information (e.g., when there is evidence indicating that a given figurine does not work, yet they have been told otherwise). However, as Schulz and Bonawitz (2007) note, their study used an implicit measure of children’s sensitivity to confounded observational evidence, meaning that the extent to which children themselves were aware of their reasons for further exploring the toy remains uncertain. More explicit measures of children’s understanding of confounding have shown that while that understanding is developing during the preschool years (Cook et al., 2011; Köksal-Tuncer & Sodian, 2018), it is not until the elementary school years that children develop a more explicit understanding of the relationship between claims and evidence (Astington, Pelletier, & Homer, 2002) and the ability to explicitly test claims in a manner that can isolate confounded causal factors (Chen & Klahr, 1999). Thus, while preschool children may be sensitive to the presence of epistemic uncertainty and engage in increased exploration in light of conflict, their insights as to when and how to resolve uncertainty in the pursuit of an explicit goal may still be developing.

Indeed, when it comes to actively seeking out empirical information with the goal of resolving a conflict between children’s intuitions and what they are told, a recent set of studies suggests a cross-culturally robust age change in children’s exploration following a surprising claim (Ronfard, Chen, & Harris, 2018, 2020; Ronfard, Ünlütabak, Bazhydai, Nicolopoulou, & Harris, 2020). Ronfard et al. (2018) presented preschool and elementary school children with a set of different-sized Russian dolls and asked them which was the heaviest. All children indicated the biggest one. The experimenter then either confirmed children’s intuition, “Yes, the biggest doll is the heaviest,” or contradicted it, “Actually, that one is not the heaviest one. The smallest one is the heaviest one.” Across age and condition, children subsequently endorsed this claim by the experimenter, even when it was counterintuitive. The experimenter then left the room, thereby allowing children to assess the experimenter’s claim empirically by picking up the dolls to compare their weights. Elementary school children significantly increased their exploration of the dolls when their intuitions had been contradicted as compared to when they had been confirmed, frequently picking up the smallest and the biggest doll concurrently to compare their relative weight—a direct test of the claim they had been given. Preschool children rarely engaged in this behavior, whether their intuitions had been confirmed or contradicted. One interpretation of these results is that seeking out information in order to confirm or disconfirm a surprising claim (as opposed to engaging in exploratory play following a surprising claim) is a later developing ability because it requires the ability to reason about how a claim could be tested and by implication the realization that some claims are empirically grounded and can be falsified.

Although this interpretation is plausible, it is premature in at least one important regard. These “doll studies” relied on a single experimental paradigm that pitted children’s prior intuitions about the relation between size and weight against a claim contradicting those prior intuitions. As Lane (2018) notes, children’s willingness to accept counterintuitive claims depends on the strengths of their initial intuitions as well as on their acquisition of certain conceptual insights, notably, the distinction between appearance and reality (Lane, Harris, Gelman, & Wellman, 2014). Thus, age-related improvements in the strength of children’s intuitions or background knowledge about the association between size and weight (Smith, Carey, & Wiser, 1985) could account for the parallel changes in children’s empirical investigation of the surprising claim that the smallest doll is the heaviest. This study makes it possible to control for children’s prior intuitions by presenting them with novel stimuli with which, irrespective of age, they all lacked prior experience. If preschool children do not spontaneously seek out further evidence when faced with a task that should motivate them to resolve a conflict between what they observed and were told, it would provide support for the claim that young children do not spontaneously think of deliberately investigating what they are told. Alternatively, if preschool children do seek out further evidence, it would suggest that young children seek out empirical evidence following surprising claims provided they conceptualize the claim as surprising.

In addition to examining whether children seek empirical evidence to resolve conflicts between what they have just observed and what they have been told, we asked whether order affects children’s processing and weighing of conflicting information: Are children more likely to investigate or endorse a claim when they hear it before versus after witnessing an event contradicting that claim. Studies directly testing the effect of order on children’s ability to weigh information from different sources are lacking because prior studies have either provided young children with testimony followed by counter (firsthand) evidence or with firsthand evidence followed by countertestimony rather than comparing both. When testimony is followed by firsthand counterevidence, children as young as 3 years of age are able to reassess their initial trust in an informant based on the conflicting evidence they have observed (Bridgers et al., 2016; Hermansen, Ronfard, Harris, Pons, & Zambrana, 2021; Scofield & Behrend, 2008). When firsthand evidence is followed by countertestimony, 4- and 5-year-olds but not 3-year-olds rely on what they saw and not what they were told (Jaswal, Croft, Setia, & Cole, 2010; Ma & Ganea, 2010). This pattern of data suggests that order may matter, at least for the youngest children, but the lack of a direct comparison of order across these studies makes it difficult to draw strong conclusions. Given the salience of more recent information (Berry, Waterman, Baddeley, Hitch, & Allen, 2018), we hypothesized that children would be more likely to seek out information relevant to an informant’s claim when counterevidence is acquired after, rather than before, the presentation of that claim.

To evaluate these hypotheses, we created a task in which children received two pieces of information about which of two figurines to use in order to make a music box work. Children were directly told by an apparently knowledgeable experimenter whether the black or the white figurine would make the music box work. They also saw a different and apparently naive experimenter place the two figurines (one after another) on the box to provide empirical evidence about which of the two figurines made the box work. After receiving these two types of information, all children were asked to sort four new figurines (2 white and 2 black figurines) into containers based on whether or not they thought the figurines could make the music box work. We made the music box available but children were not asked or encouraged to test the objects. By comparing across conditions, we could see whether, while completing the sorting task, children were more likely to place figurines on the music box when the testimony they had heard conflicted with, rather than confirmed, what they observed. We distinguished between two types of exploration: Whether children placed only one type of figurine (black or white) on the music box and whether children placed both types of figurines (black and white) on the music box. Note that only by placing both types of figurines on the music box could children obtain information that would fully resolve the conflict between what they had seen and what they had been told. Regardless of whether children placed the figurines on the music box before sorting them, we also coded whether children sorted them according to what they had seen (the pattern of activation demonstrated by the naïve experimenter who placed the figurines on the music box) and whether this sorting differed when the testimony they had heard conflicted rather than confirmed what they had seen. This design also allowed us to assess how far those who had placed both types of figurines on the music box and therefore had the necessary firsthand evidence to evaluate which figurines made the music box work was guided by this new information when sorting the figurines. Finally, after the sorting task, children were asked to make a prediction, “If I want to make the music box play one more time, which figurine should I use?” This additional question allowed us to examine any differences between how children weighed what they saw as compared to what they were told, using a verbal measure (their prediction) in addition to the two nonverbal measures (i.e., their sorting and exploration of the figurines).

To investigate the effect of information consistency, half the children received consistent information from the two sources—they were told by the apparently knowledgeable informant that only the white figurine could work, and they also observed that it was, in fact, the only one that worked when the naïve experimenter placed the white and black figurine on the music box. For the other half of children, the information was inconsistent—they were told by the apparently knowledgeable informant that only the white figurine worked, but observed during the placements by the naïve experimenter that it was, in fact, the black figurine and not the white figurine that worked.

The order in which children heard the apparently knowledgeable informant’s claim or observed the naïve informant’s placement of the figurines was counterbalanced between participants. This permitted us to examine whether the consistency and order of verbal as compared to visual information influenced children’s decision to seek further information (as reflected in their exploration of the figurines), their ongoing trust in the verbal claim (as reflected in their sorting patterns) and their reasoning about a future event (as reflected in their predictions).

Previous work indicates that although children are generally more certain about their own knowledge when it is gained from direct evidence rather than an informant’s testimony, this certainty may diminish over time (Robinson, Haigh, & Nurmsoo, 2008). To ensure that children felt equally confident in what they observed and what they were told, we took advantage of the fact that young children use information about the knowledge of informants to assess their informativeness and their actions (Bonawitz et al., 2011; Butler & Markman, 2012; Kushnir et al., 2008). By making the informant who demonstrated the toy naïve, we decreased the strength of that observational evidence. By making the informant who told children about the toy knowledgeable, we strengthened the testimonial evidence she provided. Given that children may value observational evidence more strongly than testimony (Robinson et al., 2008), we reasoned that this manipulation would “even the scale” and lead children to judge that the informativeness of the observed evidence as compared to the testimonial evidence was as equal as possible. As a result, we expected that, relative to children who received consistent information, children who received inconsistent information would be more likely to explore the figurines, less likely to sort the figurines based on what they had seen, and less likely to choose the figurine they had seen to be effective when making a prediction. Thus, we expected children’s exploration, sorting, and prediction responses to be influenced by the mismatch between visual and verbal information. Moreover, we expected these effects to reflect a recency bias (Berry et al., 2018, but see Ronfard & Lane, 2018). For children who received inconsistent information, we expected a greater influence of testimony on children’s exploration, sorting, and prediction responses when testimony was the more recent piece of information. For children who received consistent information, we expected no effect of the order of information on their performance.