The ability to understand the mental states of other individuals is central to human social behavior, yet some theory of mind capacities are shared with other species. Comparisons of theory of mind skills across humans and other primates can provide a critical test of the cognitive prerequisites necessary for different theory of mind skills to…

Does language have a role to play in conceptual development, and if so, what is that role? Understanding the contents of another person's mind parallels the development in early childhood of mental state language. Does the conceptual understanding get reflected in and drive the language development, or does the language allow the representation of…

What role does language play in developing the concept of number? This question is at the center of an important current debate. To try to answer it, one must first consider what is needed to learn number words and their meaning. First, the learner has to be able to identify number words as such, that is, to distinguish them from other sorts of…

Although prior research on the development of causal reasoning has focused on inferential abilities within the individual child, causal learning often occurs in a social and communicative context. In this paper, we review recent research from our laboratory and look at how linguistic communication may influence children's causal reasoning. First,…