Child development is today conceptualized as an essentially social
process, based on incremental knowledge acquisition driven by cultural
experience and social context. We have “social” brains. The importance of
cultural processes were recognized by the theory of Vygotsky (1978, 1986),
who also highlighted the key role of language for cognitive development.
Vygotsky argued that cognitive development did not just happen in the brain
of the individual child, but depended on interactions between the child and the
cultural “tools” available for mediating knowledge. The main cultural “tool”
(form of symbolic representation for knowledge translation, e.g., writing,
pictures, maps) discussed by Vygotsky was language, which he
conceptualized as a psychological “tool” for organizing one’s own cognitive
behaviour (e.g., via “inner speech”).