This chapter examines evidence on the relationship between language and theory of mind (ToM) reasoning. Despite wide environmental variations in exposure to language, grammar and ToM emerge spontaneously, and are employed effortlessly in typically developing children. However, there appears to be no evidence for the proposition that grammar supports the emergence of ToM, pointing to the independence of language and cognition in this respect. Rather, ToM reasoning seems to be dependent on early exposure to conversations that alert children at a very young age to the possibility that others may hold beliefs that differ from reality. It is in this sense that ToM is independent from grammar. Each can be seen as a product of a modular system that requires for the presence of both a rich innate competence and specific experiences during a critical period.
Keywords: children, critical period, grammar, language, modularity, theory of mind