Imperatives and modals
Embed Size (px)
Transcript of Imperatives and modals
Abstract Imperatives may be interpreted with many subvarieties of directiveforce, for example as orders, invitations, or pieces of advice. I argue that therange of meanings that imperatives can convey should be identified with thevariety of interpretations that are possible for non-dynamic root modals (what Icall priority modals), including deontic, bouletic, and teleological readings.This paper presents an analysis of the relationship between imperatives andpriority modals in discourse which asserts that, just as declaratives contribute tothe Common Ground and thus provide information relevant to the interpre-tation of epistemic modals in subsequent discourse, imperatives contribute toanother component of the discourse context, the addressees To-Do List, whichserves as a contextual resource for the interpretation of priority modals. Thisanalysis predicts that the interpretation of imperatives and modals in discourseis constrained in surprising ways; these predictions are borne out.
Keywords Imperatives Modality
1.1 Clause types and modals
Complete the analogy Imperatives are to deontic modals as declaratives are towhat? The answer, of course, is epistemic modals. In this paper, I will arguethat this analogy is a very strict one. That is, I claim that we should analyze therelationship between imperatives and deontic modals in a way parallel to how
P. Portner (&)Department of Linguistics, Georgetown University, Washington,DC 20057, USAe-mail: email@example.com
Nat Lang Semantics (2007) 15:351383DOI 10.1007/s11050-007-9022-y
Imperatives and modals
Published online: 13 November 2007 Springer Science+Business Media B.V. 2007
we currently think about the relationship between declaratives and epistemicmodals.
I dont believe theres much controversy concerning the relationship betweendeclaratives and epistemic modals (though people may prefer to express it interms of different terminologies or frameworks of dynamic semantics). If adeclarative is used to make an assertion, as it canonically is, and this assertion isaccepted in the conversation, the proposition it expresses becomes part of theCommon Ground. Whats in the Common Ground must be usedcounted asfactualin the interpretation of a subsequent epistemic modal. For example(I use A and B to label speakers in a conversation):
(1) A: The floor is all wet.B: It must be raining outside then.
In this example, As utterance causes the proposition that the floor is wet tobecome part of the Common Ground. After this, this proposition is amongthe facts which determine the truth conditions of Bs sentence. (There are ofcourse debates in the literature about precisely which propositions are rele-vant to the interpretation of an epistemic modal, but I think all experts onthis topic would agree that propositions in the Common Ground are amongthem.)
If the analogy is correct, our uncontroversial analysis of (1) implies thatthere is something parallel to the Common Ground to mediate the rela-tionship between imperatives and deontic modals. The concept of a To-DoList will do the job.1 According to Portner (2004) the To-Do List of anagent a is a set of properties, and the participants in the conversationmutually assume that a will try to bring it about that he or she has each ofthese properties. Typically the properties correspond to actions (e.g., [kwkx.x goes to the store in w]), and so if we are willing to be a bit imprecise, wecan say that the To-Do List represents the actions that a is committed totaking.2 The argument, then, is that the relationship between imperatives anddeontic modals should be explained as follows: imperatives contribute to aTo-Do List, in particular the To-Do List of the addressee. To-Do Lists are
1 The notion of To-Do List is similar to those of sphere of permissibility (Lewis 1979) and planset (Han 1998). However, these have not been worked out in terms of the type of ordering semanticsproposed for To-Do Lists (see Sect. 2 below).2 A To-Do List may also have properties like [kwkx. x is happy in w] or even [kwkx. there is worldpeace in w]. Which actions one needs to undertake to make these properties true of oneself is lessclear than in the case of [kwkx. x goes to the store in w], but nevertheless one can be publiclycommitted to trying. Because of properties like these, the name To-Do List is a bit inaccurate; itwould be more accurate to call it the To-Make-True-of-Me List, as pointed out to me by CraigeRoberts (p.c.). But To-Do List is more evocative of its pragmatic function.
Note that Im not taking a stand on whether actions are properties; they may only correspond toproperties. As far as I can tell, properties do the work we need in making sense of the notion of aTo-Do List, and so for purposes of this paper I dont need to worry about a formal reconstructionof actions separate from properties. See Segerberg (1990) and Lascarides and Asher (2003) forapproaches to imperatives which make crucial use of actions.
352 P. Portner
one of the contextual resources which contribute to the interpretation of adeontic modal. An example parallel to (1) is the following:
(2) A: Go present this proposal to our bankers today!B: I should take the 7 a.m. flight to New York then.
If this way of looking at imperatives is correct, we may be able to betterunderstand them by making some imperatives interact in discourse with modalsand then thinking about these modals in terms of a sophisticated theory ofmodality. As we will see in detail in Sect. 3.1, in terms of the theory of modality ofKratzer (1981) we can say that To-Do Lists help determine the ordering sourcefor the interpretation of a class of modals which includes deontic modals. Fornow, we may think of this relationship as follows: at any point in a conversation,there is a contextually salient deontic conversational background O such that, foreach property P on the addressee as To-Do List and each w compatible with theCommon Ground, P a is in Ow. Moreover, O is very likely to be used in theinterpretation of any deontic modal in the local stretch of discourse.
This link between the To-Do List and interpretation of deontic modalsis analogous to the relationship between the Common Ground and theinterpretation of epistemic modals, but there is an interesting difference.The Common Ground helps determine the modal basenot the orderingsourcefor epistemic modals. (Actually, the Common Ground helps determinethe modal base for non-epistemic modals too, as well see in Sect. 3.4.) Thisleads to the picture in Table 1. Such a view of the relationship betweendiscourse semantics and modal semantics is attractive in that it gives grammar afoothold in the conception of the ordering source. That is, whereas Kratzerthinks of the ordering source (like the modal base) as something which bringsinformation from outside of grammar into semantics, we can think of it as atleast sometimes created by grammatical means. Speakers have an explicit wayto affect the ordering source for a deontic modal: they just have to utter animperative.3
If the relationships suggested in Table 1 are correct, we have a canonicalmechanism for building up the modal base (declaratives) and a canonicalmechanism for building up the ordering source for deontic modals (impera-tives); it would provide a nice symmetry if we could find a grammaticalmechanism for helping to determine the ordering source for epistemic modals as
Table 1 Data sources for modal interpretation
Modal base Ordering source
Deontic modal Common Ground + other contextualinformation
To-Do Lists + other contextualinformation
Epistemic modal Common Ground + other contextualinformation
3 I thank Chris Barker (p.c.) for bringing this consequence of the proposal into focus for me.
Imperatives and modals 353
well. Though this is not the topic of the present paper, I speculate thatevidentials serve this function. To see why, consider Kratzers (1981) discussionof the following example:
(3) Das mu die Burgermeister-Wei-Strae sein.this must the Burgermeister-Wei-Strae beThis must be the Burgermeister-Wei-Strae.
The use of must here signals that the ordering source is not empty (sinceotherwise the sentence would be stronger than the corresponding one withoutthe modal). The ordering source in question contains information which is heldas less reliable by the speaker, for example the route description of a friend, atourist guide, or my own vague memories from years ago (Kratzer 1981: 57).From this description, it seems that its the source of information, i.e., theevidential category, which renders such conversational backgrounds less thanfully reliable, and so as appropriate for the ordering source rather than themodal base. At a more abstract level, just as we use deontic modals to combineinformation about what is the case (modal base) with information about what ispreferable (ordering source), we use epistemic modals to combine informationwere committed to (modal base) with information that we consider more orless likely (ordering source), and evidentials encode information that helps usjudge in which category a particular proposition fits.
1.2 Varieties of modal meaning
There are many ways to classify modals, but in the literature we commonly findone or both of the following: (A) a two-way distinction between epistemic androot modals, or (B) a three-way distinction among epistemic, deontic, anddynamic modals. I give examples in (4) and a summary of the classifications inTable 2:
(4) (a) It must be raining.(b) (i) John must be sent to prison. (The law says so.)
(ii) Mary should try this brand of chocolate. (She loves dark chocolate.)(iii) Susan should quit her day