For the speech of young children is subtle in its intricacies and rich in its metaphors. It is not an impoverished dialect of adult speech. Rather, it is another language altogether; impossible for adults to speak and arduous for us to understand. We might call that language ‘Childish’: we have all been fluent in Childish once, and it is a language with a billion or more native speakers today – though all of those speakers will in time forget they ever knew it.
