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Obligatory Presupposition in Discourse

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Obligatory Presupposition in Discourse Obligatory presupposition in discourse Pascal Amsili1 & Claire Beyssade2* 1Université Paris Diderot & Laboratoire de Linguistique Formelle, CNRS/2Institut Jean Nicod, CNRS Paris Some presupposition triggers, like too, seem to be obligatory in discourses where the presupposition they induce is explicitely expressed. We show that this phenomenon concerns a larger class than is usually acknowledged, and suggest that this class corresponds to the class of presupposition triggers that have no asserted content. We then propose a pragmatic explanation relying on the neo-gricean notion of antipresupposition. We also show that the phenomenon has a complex interaction with discourse relations. 1. Introduction The starting point of this work is a number of situations where some presupposition triggers seem obligatory in discourse. Here are two examples. (1) a. Jean est allé il y a deux ans au Canada. Il n’ira plus là-bas. John went to Canada two years ago. He won’t go there anymore b. #Jean est allé il y a deux ans au Canada. Il n’ira pas là-bas. John went to Canada two years ago. He won’t go there c. Léa a fait une bêtise. Elle ne la refera pas. Lea did a silly thing. She won’t re-do it. d. #Léa a fait une bêtise. Elle ne la fera pas. Lea did a silly thing. She won’t do it. *This article benefitted from comments from the audience at CiD’06 (Maynooth), and particularly from discussion with Henk Zeevat. We are also very grateful to an anonymous reviewer who provided very detailed and constructive comments. Earlier versions of this work were presented at Toulouse (PICS France-Catalunya, June 06), Bordeaux (Signes, Oct 07), Carry-le-Rouet (ANR Prélude, June 07), Boston (Syntax-Semantics Reading Group, MIT, April 08) and Paris (Ling Lunch Paris Diderot, May 2009). We also wish to thank Grégoire Winterstein and Benjamin Spector for numerous discussions, and André Bittar for his help in preparing the final version of this paper. All errors remain our own. 1 Pascal Amsili & Claire Beyssade In (1a-b), the presupposition trigger ne... plus (not anymore) is clearly preferred over the simple negation ne... pas (not).1 However, both have the same asserted content, and the presuppositional content conveyed by ne... plus does not add any- thing in this particular context, because (1a) is a clear instance of presupposition binding (van der Sandt 1992; Kamp 2001): what ne... plus could add with respect to ne... pas (i.e. John went to Canada) is part of the common ground since it was already asserted in the first clause. In other words, we are here in a situation where the speaker seems to be “forced to presuppose”, forced to use a presupposition trigger, even if this trigger doesn’t bring any new information in the context. To put it differently, we could say that in such cases, a form of informational redundancy seems obligatory, which is unexpected, redundancy being usually banned when, say, the same content is asserted twice, or even when already pre- supposed material is asserted. Here the redundancy has to be achieved by means of a presupposition trigger. Our aim in this paper is first to show that the phenomenon, which has already been described in the literature for several particles, is more general than is usually acknowledged (Section 2), then to propose a pragmatic explanation for it (Section 3), and finally to take into account the interaction of the phenomenon with discourse in general (Section 4). 2. Data We first survey in this section previous accounts of similar obligatoriness (§ 2.1), before trying to define the relevant class of presupposition triggers (§ 2.3), after having said a few more words on the importance of presupposition (§ 2.2). 2.1 Background: Obligatoriness of too and other additives 2.1.1 Kaplan Although it was not presented exactly as we have just done, this phenomenon was first observed quite a long time ago, with respect to the “obligatoriness of too’’. According to (Kaplan 1984), this observation traces back to (Green 1968). The relevant examples include the contrast in (2). 1. It turns out that in French, pas and plus are really interchangeable and cannot occur together in such contexts. So we have a strong suggestion that they form an alternative, that the speaker has to choose between the two, whereas in English, for instance, the choice would be between adding anymore or not. But we believe that what we are dealing in this paper does not depend on this idiosyncratic property of French. Obligatory presupposition in discourse 1 (2) a. Jo had fish and Mo did too b. *Jo had fish and Mo did (Kaplan 1984, p. 510) The simplest cases may suggest that we deal with syntactic constraints. However, semantics clearly plays a role, as can be seen with the next pair of examples. Here, too is not strictly obligatory, and the sentence (3b) is syntactically and semantically well-formed. However, it is pragmatically deviant, since it is suggesting that beeing seventeen is not beeing old enough to have a driver’s licence. (3) a. Barb is seventeen, and Wendy is old enough to have a driver’s license, too b. #Barb is seventeen, and Wendy is old enough to have a driver’s license (Green 1968) Kaplan’s proposal, in a nutshell, derives the obligatoriness of too from its discourse function, which is to “emphasize the similarity between members of a pair of contrast- ing items’’ (p. 516). This proposal relies crucially on the presence of a contrast, and applies only to examples like (2) where a conjunction (with and or but) is involved. 2.1.2 Krifka In a paper about stressed additive particles, (Krifka 1999) makes several comments about the obligatoriness of too. It should be noted that his paper is concerned mainly with German particles, in the particular case where they occur after their focus, as in (4). (4) Peter invited Pia for dinner, to\ o In such configurations, according to Krifka, the additive particle is always stressed (bearing a focus stress, noted with a grave accent), and it associates with a contrastive topic, itself stressed with a topic accent, noted with an acute accent. His analysis of the reason why too is obligatory in such cases relies crucially on two facts: 1. the distinction between two types of accent, the focus accent, and the con- trastive topic accent (following Büring’s work (Büring 1998) and the classical distinction from (Jackendoff 1972) between A and B accents in English) 2. the existence of an implicature, derived from a distinctiveness constraint Let us recall that the placement of the focus accent is determined by the so-called discourse coherence constraint, which stipulates that the focus accent falls on the constituent which provides a congruent answer to the question (direct and exhaustive) as in (5). (5) a. A: What did Peter eat? b. B: Peter ate pa\ sta c. B′: *Pe/ ter ate pasta 1 Pascal Amsili & Claire Beyssade When the answer is partial, there is an additional accent, the topic accent, and it is obligatory: (6) a. A: What did Peter and Pia eat? b. B: *Peter ate pa\ sta c. B′: Pe/ ter ate pa\ sta Büring has shown that answers in which there is a topic accent are answers which leave open a number of questions. So for instance, in (6), the question of what Pia ate is left open. According to Büring, such uses of the topic accent are subject to a constraint called condition of disputability. Krifka claims that another constraint comes with contrastive answers, what he calls the distinctiveness constraint, which is defined as follows: (7) If [... T...C...] is a contrastive answer to a question, then there is no alternative T′ of T such that the speaker is willing to assert [...T′... C ...]. This constraint explains why too is obligatory in contexts like (8). (8) a. A: What did Peter and Pia eat? / b. B: *Pe/ ter ate pa\ sta, and Pia ate pa\ sta / c. B′: Pe/ ter ate pa\ sta, and Piia ate pasta, to\ o The reasoning goes as follows. The first member of the answere ‘P/ ter ate pa\ sta’ is a partial answer to the question and therefore bears a topic accent. This triggers the implicature, through application of the distinctiveness constraint, that there is no alternative α to Peter such that the speaker is willing to assert ‘α ate pasta’. So, by the epistemic step usual in such reasoning, it follows that no one else but Peter ate pasta. The speaker cannot then resume his discourse with ‘Pia ate pasta’ with- out plainly contradicting himself. Krifka’s proposal is that the semantics of too is such that it allows the violation of distinctiveness by explicitly stating a discourse relation. According to Krifka, too is stressed in such contexts, because it brings a strong assertion. As a side remark, Krifka notes that another way to answer the question in (8) would be to use a conjunction as in (9). In such a case, there is no contrastive topic accent, and the speaker conforms to the maxim of manner, by preferring (9b) over (8b). (9) a. A: What did Peter and Pia eat? b. B: Peter and Pia ate pa\ sta We note that Krikfa’s reasoning relies crucially on the presence of a topic accent in the first part of the answer, and on the idea that this very accent triggers a distinctiveness implicature, which then has to be canceled via the use of the addi- tive particle. The presuppositional nature of too (and of other additive particles) doesn’t play any role.
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