..all subjects are forms of discourse and that, therefore, almost all education is a form of language education. Knowledge of a subject mostly means knowledge of the language of that subject. Biology, after all, is not plants and animals; it is a special language employed to speak about plants and animals. History is not events that once occurred; it is a language describing and interpreting events, according to rules established by historians. Astronomy is not planets and stars but a special way of talking about planets and stars, quite different from the language poets use to talk about them.