Accommodation is the process whereby a listener makes adjustments in response to behavior of the speaker. In the area of linguistics we might broadly label as theoretical pragmatics, within which we include much of formal semantics and philosophy of language, accommodation is the mechanism whereby hearers modify their representation of the conversational background so as to match assumptions that the speaker has made. The most pervasive type of accommodation involves presupposition, when a speaker takes some type of information for granted. Accommodation of presuppositions occurs when the listener adjusts their knowledge state in order to match the information that a speaker has presupposed. For example, if a speaker says, “I have to go pick up my sister from the airport,” there is a presupposition triggered that the speaker has a sister. If the listener is not already aware of the existence of the sister, they must accommodate this information by adjusting their information state accordingly. Two dominant approaches to modeling presupposition behavior have emerged in the past few decades, resulting in two broad understandings of accommodation. For a class of dynamic semantic theories, accommodation is a process that involves satisfaction in local contexts. On the other hand, a wave of research on presupposition as anaphora relies on a notion of accommodation as the creation of antecedents to enable anaphoric resolution that would otherwise fail. Within both understandings of accommodation, the particular mechanisms can also vary. Some accounts weigh the plausibility of material to be accommodated, some accounts weigh the alternative contexts within which material might be accommodated, and some weigh the amount of descriptive content contributed by the presupposition. Besides accommodation in theoretical pragmatics, a broader notion of accommodation is prominent in sociolinguistics, as well as further afield from linguistics in social psychology and anthropology. This notion includes not only the beliefs of the interlocutors, but also many other aspects of speech style and communicative behavior more generally. This literature primarily draws from communication accommodation theory (CAT), according to which a speaker adjusts their communicative behavior based on that of their interlocuter. Commonly, this adjustment involves mirroring, but interlocutors may also adjust to make differences salient rather than emphasizing similarity. While theoretical pragmatic and sociolinguistic accommodation are distinct notions with independent intellectual histories, presupposition accommodation can be seen as a special case of sociolinguistic accommodation. Both involve a hearer’s adjustment in response to a speaker. However, the former is more restrictive, concerning only adjustment to increase similarity, and only adjustment of aspects of what Lewis termed the conversational scoreboard, within which he includes the beliefs of the speaker and hearer.
Linguistic Accommodation
