Lew-Levy and Amir identify three unique mechanisms through which peer cultures shape community knowledge and drive cultural change; exploratory peer play, peer-to-peer teaching, and the propensity to maintain abandoned adult traits. We propose an additional mechanism that we believe most clearly highlights children’s role as active agents in cultural adaptation: peer disagreement. We define peer disagreements as interactions between equals who hold conflicting views and collaboratively work through their differences to resolve them. As we will argue, such interactions provide ideal conditions for the co-creation of new knowledge.

While adults often avoid open disagreement due to potential social risks (Simons & Green, Reference Simons and Green2018) – such as damaged relationships or harm to their reputation – observational studies show that preschool and elementary school children engage in disagreement with notable regularity (Laursen & Hartup, Reference Laursen and Hartup1989; Maynard, Reference Maynard1985). One reason for children’s willingness to disagree with one another may lie in the egalitarian and learning-oriented nature of these interactions. Children’s disagreements often seem to be characterized by a shared understanding that everyone involved has limited experience of the world (Piaget & Cook, Reference Piaget and Cook1952; Perret-Clermont, Reference Perret-Clermont2022) but is equally motivated to explore, learn, and generate new insights (see Liquin & Gopnik, Reference Liquin and Gopnik2022). This creates an environment where differing viewpoints are met with openness, curiosity, and a willingness to learn from one another, rather than defensiveness or fear of being proven wrong (see Dweck & Leggett, Reference Dweck and Leggett1988).

In line with this idea, recent research suggests that children view disagreements as opportunities for learning and knowledge creation (Langenhoff et al., Reference Langenhoff, Thompson, Srinivasan and Engelmann2025; Ransom, Blakey, & Ronfard, Reference Ransom, Blakey and Ronfard2025). From as young as age four – and in some cases, even age three – children who encounter disagreement, rather than agreement (e.g., about which box contains a reward), are more likely to double-check the evidence on which their beliefs are based (e.g., peeking inside the boxes; Helming, O’Madagain, & Tomasello, Reference Helming, O’Madagain and Tomasello2024; O’Madagain et al., Reference O’Madagain, Helming, Schmidt, Shupe, Call and Tomasello2022), to remember the sources of their knowledge (e.g., recalling whether they learned about the box’s content by looking inside or by being told; Baer et al., Reference Baer, Langenhoff, Keşşafoğlu, Mohtezebsade, Kidd, Küntay, Engelmann and Köymen2025; Mahr et al., Reference Mahr, Mascaro, Mercier and Csibra2021), and to reduce their confidence in their beliefs, despite being typically known for their overconfidence (Langenhoff, Srinivasan, & Engelmann, Reference Langenhoff, Srinivasan and Engelmann2024). These findings suggest that disagreement prompts young children to critically reflect on their existing beliefs – an important first step in children’s developing ability to learn and generate knowledge from disagreement.

As children get older, they develop a more nuanced understanding of disagreements, their underlying causes, and processes of resolution. Starting around age five, children increasingly judge that in disagreements over subjective matters (e.g., personal preferences), both perspectives can be right, while in disagreements over more objective issues (e.g., empirical facts), the competing perspectives can – and should – be resolved through relevant evidence (e.g., Wainryb et al., Reference Wainryb, Shaw, Langley, Cottam and Lewis2004; Yang et al., Reference Yang, Sleight, Ronfard and Harris2023). At the same age, children begin to spontaneously articulate the reasoning or evidence underlying their own beliefs when encountering disagreement from peers, and expect their peers to do the same (Köymen & Tomasello, Reference Köymen and Tomasello2018; Schleihauf et al., Reference Schleihauf, Langenhoff, Zhang, Köymen, Herrmann and Engelmannunder review). Moreover, children actively compare the evidence supporting their own and their peer’s beliefs, and rationally revise their beliefs in line with that evidence: They maintain their initial belief when their own evidence is stronger, adopt the peer’s belief when their own evidence is weaker, and suspend judgment when both have equally strong evidence (Langenhoff, Engelmann, & Srinivasan, Reference Langenhoff, Engelmann and Srinivasan2023). This emerging ability to evaluate competing perspectives in light of empirical evidence reflects a core component of scientific reasoning and constitutes a second critical step in children’s growing capacity to collaboratively generate knowledge through disagreement.

As children approach middle childhood, their reasoning about disagreement becomes even more sophisticated. By age 10, children typically understand that even when individuals have access to the same evidence, they may still disagree because they interpret that evidence differently (Amemiya, Walker, & Heyman, Reference Amemiya, Walker and Heyman2021; Amemiya, Heyman, & Gerstenberg, Reference Amemiya, Heyman and Gerstenberg2024). Around the same age, children also learn to sensibly integrate the judgments of disagreeing agents based on their respective levels of confidence (Baer, Engelmann, & Kidd, Reference Baer, Engelmann and Kidd2025). The insight that in many disagreements, both participants can be partially right or wrong – and that differing perspectives can each contribute valuable insights toward a more complete understanding of the truth – marks a third key step in children’s emerging ability to co-create knowledge from disagreement.

While much of the research so far has focused on how working through disagreement helps children acquire knowledge in domains where the answers are already known and typically taught by adults (such as determining whether an object will sink or float; Yang et al., Reference Yang, Sleight, Ronfard and Harris2023), it seems plausible that disagreement functions similarly in more open-ended domains, where there is greater potential for the co-construction of genuinely new ideas. To illustrate, consider the example from Piel (Reference Piel2012), cited by Lew-Levy and Amir, in which Japanese children explained that they “came up with the idea together” when asked how they had learned to fish for snails using straws. It is easy to imagine that this process involved disagreement. For example, one child may have suggested using a straw, while another proposed using a net to catch the snails, and it was only by combining these ideas into something new that they arrived at the most effective strategy: dislodging the snails from the rocks with the straw and scooping them with the net once they floated to the surface.

In summary, we have argued and provided initial evidence that peer disagreements constitute unique contexts for learning and the co-creation of knowledge. However, many promising directions for future research remain. For instance, it would be interesting to investigate whether the presence of disagreement enhances children’s tool innovation capacities beyond the benefits of general peer interactions shown in prior research (Gönül et al., Reference Gönül, Hohenberger, Corballis and Henderson2019). Moreover, future studies should determine whether the factors of peer disagreements we have identified as being particularly conducive to learning and knowledge creation – such as shared goals and a learning-oriented mindset (see Dweck, Reference Dweck2006) – can be manipulated to influence the outcomes of these interactions. Ultimately, we believe that a full understanding of children’s contributions to cultural adaptation must include the study of peer disagreement.