How do children come to understand that others have mental representations, e.g., of an object's location? Preschoolers go through two transitions on verbal false-belief tasks, in which they have to predict where an agent will search for an object that was moved in her absence. First, while three-and-a-half-year-olds usually fail at approach…

Symbolic representation of environmental variables is a ubiquitous and often debated component of cognitive science. Yet notwithstanding centuries of philosophical discussion, the efficacy, scope, and validity of such representation has rarely been given direct consideration from a mathematical point of view. This paper introduces a quantitative…

In the behavioral sciences, a popular approach to describe and predict behavior is cognitive modeling with adjustable parameters (i.e., which can be fitted to data). Modeling with adjustable parameters allows, among other things, measuring differences between people. At the same time, parameter estimation also bears the risk of overfitting. Are…

Bayesian orthodoxy posits a tight relationship between conditional probability and updating. Namely, the probability of an event "A" after learning "B" should equal the conditional probability of "A" given "B" prior to learning "B". We examine whether ordinary judgment conforms to the orthodox view. In three experiments we found substantial…

The ability to acquire and store generic information (that is, information about entire categories) is at the core of human cognition. Remarkably, even young children place special value on generic information, often inferring that it holds important insights about the world. Here, we tested whether children's assumptions about the nature of…

Human adults will sometimes help without being asked to help, including in situations in which the helpee is oblivious to the problem and thus provides no communicative or behavioral cues that intervention is necessary. Some theoretical models argue that these acts of "proactive helping" are an important and possibly human-specific form of…

Geometry is one of the highest achievements of our species, but its foundations are obscure. Consistent with longstanding suggestions that geometrical knowledge is rooted in processes guiding navigation, the present study examines potential sources of geometrical knowledge in the navigation processes by which young children establish their sense…

Adult humans recognize that even unfamiliar speech can communicate information between third parties, demonstrating an ability to separate communicative function from linguistic content. We examined whether 12-month-old infants understand that speech can communicate before they understand the meanings of specific words. Specifically, we test the…

The traditional cognitive developmental perspective on moral acquisition posits that children actively construct moral beliefs by assessing the negative impacts of antisocial behaviors. This account is not easily applied to actions that are considered immoral despite lacking consequences for others' welfare. We studied the moralization of…

Collaboration is fundamental to our daily lives, yet little is known about how humans come to understand these activities. The present research was conducted to fill this void by using a novel visual habituation paradigm to investigate infants' understanding of the collaborative-goal structure of collaborative action. The findings of the three…

Structural priming paradigms have been influential in shaping theories of adult sentence processing and theories of syntactic development. However, until recently there have been few attempts to provide an integrated account that explains both adult and developmental data. The aim of the present paper was to begin the process of integration by…

When students learn scientific theories that conflict with their earlier, naive theories, what happens to the earlier theories? Are they overwritten or merely suppressed? We investigated this question by devising and implementing a novel speeded-reasoning task. Adults with many years of science education verified two types of statements as quickly…

The elicited-response false belief task has traditionally been considered as reliably indicating that children acquire an understanding of false belief around 4 years of age. However, recent investigations using spontaneous-response tasks suggest that false belief understanding emerges much earlier. This leads to a developmental paradox: if young…

The integrated use of spatial and temporal information seems to support the separation of two sensory streams. The present study tested whether this facilitation depends on the encoding of sensory stimuli in externally anchored spatial coordinate systems. Fifty-nine children between 5 and 12 years as well as 12 young adults performed a crossmodal…

To become cooperative members of their cultural groups, developing children must follow their group's social norms. But young children are not just blind norm followers, they are also active norm enforcers, for example, protesting and correcting when someone plays a conventional game the "wrong" way. In two studies, we asked whether young children…