Despite the remarkable achievements in commonsense psychology that we reviewed in chapter 7, there is no question that the most significant developmental advance in the second year of life is the acquisition of language. For most children, it is during the second year that they become adept and sophisticated users of language, and it is language that does the lion’s share of the work in transforming the baby into the child. With language, the scope of social engagement expands enormously. Children first learn to use words to refer to objects and then events that are around them. Before long, they are able to share interactions with others about topics that are no longer tied to the concrete objects in their immediate environments. They are able to communicate about absent objects, about the past and the future, and about imaginary things. They are able to communicate about themselves and their beliefs, desires, and feelings. With language children are prepared to take up their role as a fully functioning member of the symbolic species (Deacon, 1997).