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1 Alex Goebel 620 Spring 2016 Paper Presentation of von Fintel & Gillies (2010) Synopsis Must... stay... strong! Von Fintel & Gillies (vf&g) argue against a weakened semantics of must and propose an alternative analysis that implements an evidentiality component via a presupposition 1. The (=Karttunen s) Problem, including something about evidentiality Karttunen s Problem on the standard account for modals, must is a universal quantifier over possible worlds (and crucially reflexive 1 ) such that [must p] p (1) Where are the keys? a. They must be in the kitchen drawer. b. They are in the kitchen drawer. however, according to basic intuitions (1a) is not stronger (and possibly weaker) than (1b) vf&g argue furthermore that must has an evidential component such that it signals that the speaker has reached her conclusion via an indirect inference this explains why must is odd in the direct evidence scenario in (2) but okay in the indirect evidence scenario in (3) (2) [Seeing the pouring rain] b.??it must be raining. (3) [Seeing wet rain gear and knowing rain is the only possible cause] b. It must be raining. note that what is defined as direct and indirect is depending on the context: in a Matrix-like scenario where the reliability of human sense perception is highly dubious, the direct scenario in (2) seems to turn into an indirect scenario, thus licensing use of must: (4) [Seeing the pouring rain] It must be raining. 1 A reflexive relation is one which includes the starting world in its scope.

2 2. Two (allegedly failing) approaches 2.1 The comment account by Westmoreland Westmoreland proposes an analysis for must as indicating an inference as the source of knowledge on a non truth-conditional level however, embedding under a question as in (5) shows that must indeed operates at the truth-conditional level since it scopes below the question operator (5) [Pascal and Mordecai are playing Mastermind. Pascal asks:] Must there be two reds? = Is it the case that the evidence entails that there are two reds? Is it the case that there are two reds? & speaker inferred this proposition Brief Excursion: How would non truth-conditional content look like? a paradigmatic example for non truth-conditional content are expressives like damn in (6) (6) Does the damn paper show any evidence? Is it the case that the damn paper shows any evidence? = Is it the case the the paper shows any evidence? & speaker has negative attitude towards the paper in contrast to (5), answering the question in (6) with Yes would not commit to the acceptance of the expressive damn 2.2 Kratzer s ordering source (aka. The True Competitor) the (standard) solution to Karttunen s problem comes from Kratzer s combination of an ordering source with a modal base according to this view, (1a) does not entail (1b) because we have a stereotypical ordering source that takes into consideration (possibly weird) possibilities such that [must p] p no longer holds Reminder of the proposed truth conditions for epistemic must It must be raining is true in a world w iff w W: if everything we know about w is also true in w and nothing that is abnormal in w occurs in w, then it is raining in w. or w MAX< [ λp : p is a reasonable expectation in w ] ( {p : p is known in w }). it is raining in w For all worlds w in the following set, it is raining in w Those worlds, from the set of worlds where everything we know about w is true which satisfy the greatest number of our reasonable expectations in w 2

3 3. The (not so convincing) Evidence against weak 2 must Case 1: Indirectness Weakness (aka. Beating Up The Strawman) vf&g criticize that weakness does not follow from the indirectness signal and would thus require further argumentation Important note: intuitively, it seems obvious that indirect evidence is weaker than direct evidence however, what is crucial here is the logical sense: it doesn t matter whether something follows from indirect or direct evidence as long as it follows! Case 2: Chris Balls in a scenario like (7) we have a closed set of possibilities, thus must cannot be weak here (7) [Chris is missing a ball and knows it to be in either of three boxes A, B and C] The ball is in A or in B or in C. It is not in A.... It is not in B. So, it must be in C. (cf.?so, it is in C.) 3 as long as we don t see the ball in the box, there is still room for black magic to happen Case 3: No Doubt in a scenario like (8) the speaker explicitly states his lack of doubt, thus... (8) A: They said it was going to rain. I wonder whether it has started. B: I don t think so, it was still dry when I came in 5 minutes ago. A: Look, they re coming in with wet umbrellas. There is no doubt at all. It must be raining now. 1 this argument is resting on implicit assumptions about the meaning of the no doubt-phrase: taking its contribution to be the emptying of the stereotypical ordering source seems dubious 2 vf&g mention a Gricean explanation for this fact in a footnote which states that statements of certainty implicate that the speaker isn t that certain after all 2 Note that in the standard account, must isn t weak in the strict sense: It s still a universal quantifier over possible worlds. Thus the scarequotes. Since this is troublesome for basically every argument vf&g put forth I ll just point it out here and we ll keep it in mind for the rest. 3 For the remainder of this handout, this will be the official symbol to indicate me complaining about vf&g. 3

4 Case 4: Modus Ponens a logically valid inference like (9) is not compatible with any weak semantics for must (9) If Carl is at the party, then Lenny must be at the party. Carl is at the party. So: Lenny is at the party. 1 one might wonder whether the So: is doing the trick here 2 furthermore, this argument relies on a certain semantics for conditionals 3 why is it possible to have must in the conclusion in (10)? and why is the inference from must p to p in such a scenario odd, see (10)? (10) If Carl is at the party, then Lenny must be at the party. Carl is at the party. So: Lenny must be at the party. (10) If Carl is at the party, then Lenny must be at the party. Carl is at the party. So: Lenny must be at the party.??so: Lenny is at the party. Case 5: Weak Modals combining must with weak modals as in (11) has a contradictory flavor which is easily explained if must is strong (11) a. #It must be raining but perhaps it isn t raining. b. #Perhaps it isn t raining but it must be. the ordering source account for modals can easily explain these data as the following truth conditions show: It must be raining but perhaps it isn t raining is true in a world w iff w MAX<[...]. it is raining in w & 4 w MAX<[...]. it is not raining in w For all worlds w in MAX<[...], it is raining in w & there is a world w in the same set MAX<[...] such that it is not raining in w as long as the set both modals quantify stays the same, (11) yields a contradiction however, if we quantify over different sets via special prosody (11a) or explicit conversational background (11b), the contradictory flavor disappears: (11) a. It MUST be raining but PERHAPS it ISN T raining. b. Given that rain is the only explanation for the wet gear, it must be raining, but it might not be raining if we assume there s a child playing pranks. 4 Semantically, but is assumed to function as a conjunction. 4

5 Case 6: Billy Being Annoying the semantics of weak modals does not commit one to the proposition expressed, thus (12c) is a reasonable response to Billy s oddness a similar response in (13c) however seems odd with must, thus it cannot be weak (12) a. Alex: It might be raining. b. Billy: [Opens curtains] No it isn t. You were wrong. c. Alex: I was not! Look, I didn t say it was raining. I only said it might be raining. Stop picking on me! (13) a. Alex: It must be raining. b. Billy: [Opens curtains] No it isn t. You were wrong. c. Alex: #I was not! Look, I didn t say it was raining. I only said it must be raining. Stop picking on me! is (13c) really that bad? And if so, isn t it Billy who makes things weird? 4. Nonetheless, The Proposal vf&g propose a combination of standardly strong must with an evidential component they take this evidential component to be a lexically specified presupposition for the following reasons: (i) non at-issueness (ii) persistence under negation, see (14) (iii) Wait a minute -test, see (15) (14) There can t be two reds. (15) a. Alex: It must be raining. b. Billy: Hey! Wait a minute. Whaddya mean, must? Aren t you looking outside? the basic proposal goes as follows: Some Formalism, Part I Definition 1 (Kernels and bases) K is a kernel for B K, B K is determined by the kernel K, only if: i. K is a set of propositions (if P K then P W) ii. B K = K Definition 2 (Strong must + evidentiality). Fix a c-relevant kernel K: i. [[must p]] c,w is defined only if K does not directly settle [[p]] c ii. If defined, [[must p]] c,w = 1 iff B K [[p]] c 5

6 Decoding the definitions: 1) we maintain a strong semantics for must s.t. [[must p]] = w W. p holds in w 2) we introduce an element, let s call it kernel, that contains all direct (enough) information 3) additionally, must has a presupposition which requires the information in the kernel not to settle the proposition ( one might wonder how the kernel is different from an ordering source) what is now left to resolve is the fuzziness regarding the settlement of a proposition vf&g propose two implementations of which I will report only the first one: Formalism, Part II Implementation 1 (Explicit representation) K directly settles whether P iff either X P or X P = ø for some X K. A proposition is directly settled by a kernel iff the kernel contains a propositions that entails or contradicts it as an illustration consider our direct and indirect scenarios from above: (2) [Seeing the pouring rain] b.??it must be raining. (3) [Seeing wet rain gear and knowing rain is the only possible cause] b. It must be raining. in the direct scenario in (2) the kernel contains the proposition It is raining, thus uttering (2b) yields a presupposition failure in the indirect scenario in (3) the kernel contains the proposition people are wearing wet rain gear, thus no proposition in the kernel does either entail or contradict the modalized proposition it is raining and must p is fine there is still some fuzziness as to how propositions jump into the kernel but this is a problem that we have with conversational backgrounds and modal bases just as well 5. Conclusion vf&g argue that must has to keep a strong modal semantics their proposal includes a standard universal force in combination with a evidential component in the form of a lexically specified presupposition the presupposition gets violated in case there is information available that settles the proposition in question, this being implemented via entailment from a set of propositions however, one might wonder how any of their evidence could not be handled by a standard combination of ordering source and modal base 6

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