THE DEVELOPMENT OF THE STRONG OBLIGATION SYSTEM IN AMERICAN ENGLISH

USING A DATABASE of 23 plays written since 1824, this paper describes in detail the functions of the three strong obligation markers got to, have to, and must in American English. I show that got to is used for obligations motivated by the personal interests of the speaker, have to for obligations which are objective and logical, and must for oblig ations associated with societal expectations and interpersonal relatio ns. The relative frequencies of these markers have changed drastically in the last 170 years, and I argue that this is related to other chan ges in the modal system, which have brought about (1) increases in the frequency of medals with ''individual'' meaning (got to, should, and intentional gonna) and ''objective'' meaning (have to, epistemic must, and predictive gonna), as well as medals denying personal responsibil ity (have to and can't), and (2) corresponding decreases in the freque ncy of medals reflecting societal norms (obligation must, intentional will, and ought) and the speaker's assumptions about responsibility fo r events affecting others (shall). I consider the increases and decrea ses in the relative frequencies with which these forms have been used as evidence of a general pattern of change in frequencies with which d ifferent meanings are expressed in the language.