The Language Instinct: How the Mind Creates Language

by Steven Pinker

learning a grammar from examples requires a special similarity space (defined by Universal Grammar). So does learning the meanings of words from examples, as we saw in Quine’s gavagai problem, in which a word-learner has no logical basis for knowing whether gavagai means “rabbit,” “hopping rabbit,” or “undetached rabbit parts.” What does this say about learning everything else? Here is how Quine reports, and defuses, what he calls the “scandal of induction”: It makes one wonder the more about other inductions, where what is sought is a generalization not about our neighbor’s verbal behavior but about the harsh impersonal world. It is reasonable that our [mental] quality space should match our neighbor’s, we being birds of a feather; and so the general trustworthiness of induction in the…learning of words was a put-up job. To trust induction as a way of access to the truths of nature, on the other hand, is to suppose, more nearly, that our quality space matches that of the cosmos…. [But] why does our innate subjective spacing of qualities accord so well with the functionally relevant groupings in nature as to make our inductions tend to come out right? Why should our subjective spacing of qualities have a special purchase on nature and a lien on the future? There is some encouragement in Darwin. If people’s innate spacing of qualities is a gene-linked trait, then the spacing that has made for the most successful inductions will have tended to predominate through natural sel...