It is tempting to explicate the mastery of language, as many philosophers have, with how we come to learn language. Interpreting how we come to learn a language necessarily involves saying what the mind's relevant capacities are. Too long we have been told that those capacities are adaptive to, as well as within, a social context; it seemed plausible to argue that we learn to have (propositional) thoughts as we learn and use the language conatively. This essay tries to persuade the reader that there is something else besides, something that cannot be taught. That something, elusive as it is, is caught in one of the phrases with which the OED defines passion, 'An eager outreaching of the mind towards something'. Passion understood in this way is conceptually indispensable to human language.