“In our social relations, the race is not to the swift but to the verbal – the spellbinding orator, the silver-tongued seducer, the persuasive child who wins the battle of wills against a brawnier parent.”

I have always assumed that we learn language. Steven Pinker thinks otherwise, and in his book he argues that though we may learn words and the superstructure of an individual language, language in general is something we instinctively do.

Though this is well out of my usual interests, the evidence seems compelling. Children will make consistent errors as they learn languages, errors they cannot have overheard an adult say: “Don’t giggle me” or “we holded the baby rabbits.” Language complexity is universal, Pinker suggests, because children reinvent it every generation. This is why children of parents who speak a language only very poorly, like deaf children whose parents speak very poor sign language, will without further input still end up using advanced and very complex signing rules, ones their parents do not use correctly. They shut out the errors of their parents and develop their own rules.

Languages have far fewer synonyms than we believe: most things we call synonyms actually have slightly different meanings. Children, Pinker points out, intuitively understand this. If you give a child a picture of pewter tongs, call it biff, and ask them to pick out another biff, they’ll pick out plastic tongs: they associate biff with tongs, because they don’t know the word. If you give them a picture of a pewter cup and repeat the process, children will pick out a pewter spoon as being biff. Since they already know the word cup, they assume biff is the material.

Why does it all matter? Pinker worries we tend to undervalue the importance of nature and overvalue the importance of environment in human development. Of course, both matter, and language neatly captures this interaction. Nature provides structure and underlying rules: environment determines which language we learn.