Modals and conditionals Kai von Fintel (MIT) CSSL17 July 1014, - - PowerPoint PPT Presentation

modals and conditionals
SMART_READER_LITE
LIVE PREVIEW

Modals and conditionals Kai von Fintel (MIT) CSSL17 July 1014, - - PowerPoint PPT Presentation

Modals and conditionals Kai von Fintel (MIT) CSSL17 July 1014, 2017 1 This intermediate level course introduces the semantics of modals and conditionals and provides a guide to current research in the area. 2 http://kvf.me/crete


slide-1
SLIDE 1

Modals and conditionals

Kai von Fintel (MIT) CSSL17 — July 10–14, 2017

1

slide-2
SLIDE 2

This intermediate level course introduces the semantics of modals and conditionals and provides a guide to current research in the area.

2

slide-3
SLIDE 3

http://kvf.me/crete

includes links to these slides, readings, and Slack channel

3

slide-4
SLIDE 4

How to participate:

  • listen & think
  • ask questions (in class, on Slack)
  • consider other languages
  • stay in touch

4

slide-5
SLIDE 5
  • 0. Introduction
  • 1. Modals
  • 2. Conditionals
  • 3. Interactions
  • 4. Ask me anything
  • 5. X

5

slide-6
SLIDE 6
  • 0. Introduction

6

slide-7
SLIDE 7
slide-8
SLIDE 8
slide-9
SLIDE 9
slide-10
SLIDE 10
slide-11
SLIDE 11
slide-12
SLIDE 12
slide-13
SLIDE 13

(1) A former meerkat expert at London Zoo has been ordered to pay compensation to a monkey handler she attacked with a wine glass in a love spat over a llama-keeper.

[Associated Press, Oct. 14, 2015]

13

slide-14
SLIDE 14

The sentence “A former meerkat expert at London Zoo has been ordered to pay compensation to a monkey handler she attacked with a wine glass in a love spat over a llama-keeper.” is true if (and only if) a former meerkat expert at London Zoo has been ordered to pay compensation to a monkey handler she attacked with a wine glass in a love spat over a llama-keeper.

14

slide-15
SLIDE 15

Meanings of sentences

  • describe the world
  • distinguish between ways the world may be, matching

some of them, not matching others

15

slide-16
SLIDE 16

“Ways the world may be” = possible worlds

16

slide-17
SLIDE 17
  • Assertions make claims about what the world is like.
  • Questions ask what the world is like.
  • Commands order changes in what the world is like.

17

slide-18
SLIDE 18

There are many ways the world may be.

18

slide-19
SLIDE 19

Language is a precision instrument to distinguish between many possible ways the world may be.

19

slide-20
SLIDE 20

Our job as semanticists: Reverse engineer this precision instrument.

20

slide-21
SLIDE 21

Meanings come about through a combination of

  • individual elements of meaning
  • the hierarchical syntactic structure they occur in
  • principles of meaning composition
  • inferences about the situation an expression is used in

21

slide-22
SLIDE 22

Two (or three) kinds of elements of meaning:

  • content words (chair, love, ponder, incandescent, …)
  • “function”/logical words (the, most, and, if, might, …)
  • and maybe: structural configurations.

22

slide-23
SLIDE 23

Oh, those big little words!

23

slide-24
SLIDE 24

After cataloguing various ‘improper’ senses of only, Ockham remarks that These are the senses, then, in which the exclusive expression can be taken improperly. And perhaps there are still other senses in which it can be taken

  • improperly. But since they are not as widely used as

the ones we have dealt with, I will leave them to the specialists. “A glorious picture indeed: monasteries crammed to the spires with specialists on only, laboring away on the fine points of the semantics of exclusive propositions. Those were the days!” (Larry Horn)

24

slide-25
SLIDE 25

So, with the throttling hands of death at strife, Ground he at grammar; Still, thro’ the rattle, parts of speech were rife: While he could stammer He settled οτι’s business — let it be! — Properly based ουν — Gave us the doctrine of the enclitic δε, Dead from the waist down. Robert Browning: “A Grammarian’s Funeral”

25

slide-26
SLIDE 26

… in this chapter we shall consider the word “the” in the singular, and in the next chapter we shall consider the word “the” in the plural. It may be thought excessive to devote two chapters to one word, but to the philosophical mathematician it is a word of very great importances: like Browning’s grammarian with the enclitic δε, I would give the doctrine of this word if I were “dead from the waist down” and not merely in prison. Bertrand Russell: “Introduction to Mathematical Philosophy”

26

slide-27
SLIDE 27

The word “if”, just two tiny letters Says so much for something so small The biggest little word in existence; Never answers, just questions us all If regrets were gold, I’d be rich as a queen If teardrops were diamonds, how my face would gleam If I’d loved you better, I wouldn’t be lonely If only, if only, if only Dolly Parton: “If only”

27

slide-28
SLIDE 28

If

28

slide-29
SLIDE 29

(2) If it had rained, I would have used an umbrella.

29

slide-30
SLIDE 30
  • the if-clause sets up a hypothetical scenario
  • the consequent is used to characterize the scenario

30

slide-31
SLIDE 31

The world as it would have been like if it had rained is a world where I used an umbrella.

31

slide-32
SLIDE 32

if p takes us to the world that is just like the actual world in all respects other than that p is true (and whatever is needed to make p true) the consequent q is then used to describe the world that if p took us to

32

slide-33
SLIDE 33

1.3 Variably Strict Conditionals

(A) VACUOUS TRUTH (B) NON-VACUOUS TRUTH (C) FALSITY- - OPPOSITE TRUE

(D) FALSITY - - OPPOSITE FALSE

FIGURE 3

slide-34
SLIDE 34

(3) If Caesar had fought the Korean War, he would have used catapults. vs. (4) If Caesar had fought the Korean War, he would have used nuclear weapons.

34

slide-35
SLIDE 35

http://youtube.com/watch?v=0lpY0Kt4bn8

35

slide-36
SLIDE 36

(5) If kangaroos had no tails, they would topple over.

36

slide-37
SLIDE 37

What use are claims about other possible worlds?

37

slide-38
SLIDE 38

(6) If there was an earthquake tomorrow, this house would collapse.

38

slide-39
SLIDE 39

(6) If there was an earthquake tomorrow, this house would collapse. In a world just like ours (where the house is built the same way, the same laws of physics apply, …) but where there is an earthquake, this house collapses.

39

slide-40
SLIDE 40

Initial insights: the semantics for conditionals/modals

  • needs to be context-dependent
  • needs to be subject to contextual indeterminacy
  • needs to anchor the claim to the actual world

40

slide-41
SLIDE 41

A bit about the framework

41

slide-42
SLIDE 42
  • Heim & Kratzer 1998
  • von Fintel & Heim 2017

42

slide-43
SLIDE 43
  • Each expression has a semantic value (extension) relative

to a possible world (evaluation world): [ [α] ]w

  • Each expression has an intension, a function from worlds

to its extension relative to that world: λw. [ [α] ]w

  • The extension of a complex expression is calculated

compositionally from the extensions/intensions of its immediate constituents.

43

slide-44
SLIDE 44

An utterance of a sentence φ in a world w is true iff [ [φ] ]w = 1.

44

slide-45
SLIDE 45

The context set of a conversation is the set of worlds that are still candidates for being the world the conversation is happening in. Asserting a sentence φ is a proposal to eliminate any world w from the context set such that [ [φ] ]w = 0.

45

slide-46
SLIDE 46

Modals, finally

46

slide-47
SLIDE 47
slide-48
SLIDE 48

must, have to, should, ought to, may, might, can, could, need

48

slide-49
SLIDE 49

Two dimensions of modal meaning:

  • modal force (necessity … possibility)
  • modal flavor (epistemic, deontic, …)

49

slide-50
SLIDE 50

(7) It has to be raining. (8) Visitors have to leave by six pm. (9) You have to go to bed in ten minutes. (10) I have to sneeze. (11) To get home in time, you have to take a taxi.

50

slide-51
SLIDE 51
  • Modals are quantifiers over possible worlds.
  • Which possible worlds they quantify over constitutes their

flavor.

51

slide-52
SLIDE 52
  • Force = quantificational strength (universal … existential)
  • Flavor = type of anchoring

52

slide-53
SLIDE 53

The general schema: M [f(w)] (φ) M the quantificational relation between two sets of possible worlds f(w) a set of possible worlds assigned by flavor f to the evaluation world w φ the prejacent proposition, a set of worlds where φ is true

53

slide-54
SLIDE 54

(12) It has to be raining. M universal quantification (subset relation) f(w) the set of worlds compatible with the evidence in w φ the set of worlds where it is raining ⇝ the evidence in w entails that it is raining

54

slide-55
SLIDE 55

(13) Iris can have one cookie after dinner. M existential quantification (compatibility relation) f(w) the set of worlds that satisfy the parental wishes in w φ the set of worlds where Iris has one cookie after dinner ⇝ the parental wishes in w allow Iris to have one cookie after dinner

55

slide-56
SLIDE 56

From syntax to interpretation:

  • how does the modal get a prejacent proposition to work
  • n?
  • where does the flavor f(w) come from?

Lots of implementation options. But core insight is important.

56

slide-57
SLIDE 57

Modals and conditionals — Day Two

57

slide-58
SLIDE 58

Reminder

58

slide-59
SLIDE 59

http://youtube.com/watch?v=0lpY0Kt4bn8

59

slide-60
SLIDE 60

Initial insights: the semantics for conditionals/modals

  • needs to be context-dependent
  • needs to be subject to contextual indeterminacy
  • needs to anchor the claim to the actual world

60

slide-61
SLIDE 61

The general schema for modals: M [f(w)] (φ) M the quantificational relation between two sets of possible worlds f(w) a set of possible worlds assigned by flavor f to the evaluation world w φ the prejacent proposition, a set of worlds where φ is true

61

slide-62
SLIDE 62

Simple flavors:

  • epistemic (worlds compatible with the evidence)
  • deontic (worlds that satisfy the rules)

62

slide-63
SLIDE 63

Complex flavors

63

slide-64
SLIDE 64

(14) Howard forgot to return his library book. He has to pay a $5 fine. complex flavor: the actual world circumstances + what the rules are

64

slide-65
SLIDE 65

essentially complex:

  • not just the circumstances: Howard may be a scofflaw who

never pays fines

  • not just the rules: Howard would not have failed to return

the book

65

slide-66
SLIDE 66

insight: flavors can be complex implementation: lots of options

66

slide-67
SLIDE 67

Famously, Kratzer relativized the semantics of modals to two parameters:

  • modal base (core flavor)
  • ordering source (comparing worlds in the modal base)

67

slide-68
SLIDE 68

68

slide-69
SLIDE 69

Iteration

69

slide-70
SLIDE 70

(15) Cosette might have to be home by midnight. One modal embedded under the other:

  • epistemic might
  • deontic have to

70

slide-71
SLIDE 71

might f1(w) [ λw′. have to f2(w′) Cosette be home by midnight ] ⇝ the evidence leaves open that Cosette is required to be home by midnight

71

slide-72
SLIDE 72

More on strength

72

slide-73
SLIDE 73
  • there are many kinds of quantifiers over individuals

(including cardinals, proportional, …)

  • modals show less variety

73

slide-74
SLIDE 74

Weak necessity: (16) I don’t have to work on this tonight but I should.

74

slide-75
SLIDE 75

75

slide-76
SLIDE 76

von Fintel & Iatridou 2008:

  • weak necessity modals are necessity modals with an

additional narrowing of their domain

76

slide-77
SLIDE 77

Rubinstein 2014:

  • must/have to are sensitive to non-negotiable priorities
  • nly
  • should/ought to are sensitive to further priorities

(i.e. negotiable)

77

slide-78
SLIDE 78

Rullmann, Matthewson & Davis 2008:

  • narrowing of domain can make necessity modals as weak

as possibility modals

78

slide-79
SLIDE 79

Deal 2011:

  • when a language doesn’t have a necessity modal, the

possibility modal can fill the void

79

slide-80
SLIDE 80

von Fintel & Gillies 2010 vs. Lassiter 2016: Is epistemic must weaker than the bare prejacent?

80

slide-81
SLIDE 81

(17) It must be raining. vs. (18) It’s raining.

81

slide-82
SLIDE 82
  • 2. If (again)

82

slide-83
SLIDE 83

(19) If Rosa left before 6am, she got there in time.

  • epistemic flavor
  • worlds compatible with the evidence + where Rosa left

before 6am

  • all of those worlds are worlds where she got there in time

83

slide-84
SLIDE 84

Just like modals:

  • quantificational force (universal)
  • modal flavor (epistemic)
  • anchoring to actual world (actual evidence)

plus: restriction to worlds where the antecedent is true

84

slide-85
SLIDE 85

Obvious idea: if is a modal operator

85

slide-86
SLIDE 86

if [f(w)] (p) (q)

  • the antecedent p
  • the modal flavor function f(w)
  • the consequent q

true iff ∀w′ ∈ p ∩ f(w): q(w′) = 1.

86

slide-87
SLIDE 87

An alternative (closer to what we said in the intro):

  • if p is a plural definite description of the p-worlds of a

certain flavor

  • the consequent is claimed to be true in those worlds

87

slide-88
SLIDE 88

if [f(w)] (p) = the plurality of worlds that contains the p-worlds in f(w)

88

slide-89
SLIDE 89

What happens when we combine the if p-plurality of worlds with the consequent proposition?

  • the consequent is a function from individual worlds to

truth-values

  • it can’t be directly applied to a plurality of worlds

The same thing happens in the case of pluralities of individuals!

89

slide-90
SLIDE 90

(20) The students laughed.

  • the students denotes a plurality of individuals (made up
  • f all and only the students)
  • laughed is a predicate of single individuals

The combination needs to be mediated.

90

slide-91
SLIDE 91

The students * laughed The *-operator “pluralizes” a predicate. The resulting plural predicate is true of a plurality iff the original predicate is true

  • f every atom making up the plurality.

91

slide-92
SLIDE 92

if p, * q true iff q is true of every world in the plurality of worlds denoted by if p (or more precisely, if f(w) p).

92

slide-93
SLIDE 93

Conditionals as plural definite descriptions:

  • Schlenker 2004

93

slide-94
SLIDE 94

Xs and Os

94

slide-95
SLIDE 95

(21) If Rose scored, we won. (22) If Rose had scored, we would have won. Sometimes: indicative vs. subjunctive Sometimes: indicative vs. counterfactual

95

slide-96
SLIDE 96

(21) If Rose scored, we won. (22) If Rose had scored, we would have won. Sometimes: indicative vs. subjunctive Sometimes: indicative vs. counterfactual

95

slide-97
SLIDE 97

Not always subjunctive: (23) If Rose had scored, we would have won.

English has no subjunctive

96

slide-98
SLIDE 98

Not always counterfactual: (24) a. If he had taken arsenic, he would be showing exactly these symptoms.

Anderson 1957

b. If she brought pie, we would eat it rightaway.

future less vivid (FLV)

97

slide-99
SLIDE 99

Again, not counterfactual: (25) The murderer used an ice-pick. But, if the butler had done it, he wouldn’t have used an ice-pick. So the murderer must have been someone else.

Stalnaker 1975

98

slide-100
SLIDE 100

We need neutral terminology. O-marking: ordinary, open, “indicative” conditionals X-marking: the extra marking on counterfactuals, FLVs, etc.

99

slide-101
SLIDE 101
  • What meaning does X-marking contribute?
  • How does it achieve the meaning it contributes?

100

slide-102
SLIDE 102

Iatridou 2000: X-marked conditionals quantify over a domain

  • f worlds that excludes the actual world.

101

slide-103
SLIDE 103

But Mackay 2015: (26) a. If Jones had taken arsenic, things wouldn’t be quite as they actually are. b. If Jones had taken arsenic, everything would be exactly as it actually is.

102

slide-104
SLIDE 104

Modus ponens: (27) A: If Heather had left before 9am, she would have made it to the meeting. B: Well, you’re wrong. She did leave before 9 and still didn’t make it.

103

slide-105
SLIDE 105

For all conditionals: the domain of quantification must include antecedent worlds. The meaning of O-marking:

  • The domain of quantification is entirely within the context

set. The meaning of X-marking:

  • The domain of quantification is not entirely within the

context set.

104

slide-106
SLIDE 106
  • von Fintel 1998: X-marking triggers non-inclusion

presupposition

  • Leahy 2017: X-marking has no meaning, triggers

counterfactuality implicature when in competition with O-marking

105

slide-107
SLIDE 107

How do O/X-marking have the meaning they do? As Iatridou 2000 showed, X-marking is complex:

  • an extra layer of past, not obviously temporal
  • often a future morpheme (in the consequent)
  • often a “fake” aspect, not obviously temporal
  • often subjunctive mood

We don’t understand much yet how these interact. Most work has been done on the role of past tense.

106

slide-108
SLIDE 108

For now: if O(f(w) p)(q) signals that f(w) ∩ p ⊆ cs if X(f(w) p)(q) signals that f(w) ∩ p ̸⊆ cs

107

slide-109
SLIDE 109

Ordering in conditional semantics

108

slide-110
SLIDE 110

(Failure of?) Strengthening the Antecedent: (28) a. If Sophie had gone to the parade, she would have seen Pedro. b. If Sophie had gone to the parade and and been stuck behind a tall person, she would have seen Pedro.

109

slide-111
SLIDE 111

Sobel Sequence: (29) If Sophie had gone to the parade, she would have seen Pedro; but if she had gone to the parade and and been stuck behind a tall person, she would not have seen Pedro.

110

slide-112
SLIDE 112

Lewis: “our problem is not a conflict between counterfactuals in different contexts, but rather between counterfactuals in a single context. It is for this reason that I put my examples in the form of a single run-on sentence, with the counterfactuals

  • f different stages conjoined by semicolons and but.”

111

slide-113
SLIDE 113

Lewis: “It is still open to say that counterfactuals are vague strict conditionals based on similarity, and that the vagueness is resolved-the strictness is fixed-by very local context: the antecedent itself.That is not altogether wrong, but it is

  • defeatist. It consigns to the wastebasket of contextually

resolved vagueness something much more amenable to systematic analysis than most of the rest of the mess in that wastebasket.”

112

slide-114
SLIDE 114

Edgington: “a piece of masonry falls from the cornice of a building, narrowly missing a worker. The foreman says: (30) If you had been standing a foot to the left, you would have been killed; but if you had (also) been wearing your hard hat, you would have been alright.

113

slide-115
SLIDE 115

Edgington: “the building foreman’s remarks above […] constitute a single, pointful piece of discourse”

114

slide-116
SLIDE 116

Reverse Sobel: (31) #If Sophie had gone to the parade and been stuck behind a tall person, she would not have seen Pedro; but if she had gone to the parade, she would have seen Pedro.

115

slide-117
SLIDE 117

(32) a: If Sophie had gone to the parade, she would have seen Pedro; but if she had gone to the parade and and been stuck behind a tall person, she would not have seen Pedro. b: But then she wouldn’t necessarily have seen Pedro, right?

116

slide-118
SLIDE 118
  • von Fintel 2001
  • Gillies 2007
  • Moss 2012
  • Holst 2013
  • Klecha 2014
  • Dohrn 2017
  • K. Lewis 2017

117

slide-119
SLIDE 119

Modals and conditionals — Day Three

118

slide-120
SLIDE 120

Reminders and Clarifications

119

slide-121
SLIDE 121

The general schema for modals: M [f(w)] (φ) M the quantificational relation between two sets of possible worlds f(w) a set of possible worlds assigned by flavor f to the evaluation world w φ the prejacent proposition, a set of worlds where φ is true

120

slide-122
SLIDE 122

Complex flavors: (33) Howard has to pay a fine. quantifies over worlds

  • where the same things happened as in the evaluation

world

  • and that afterwards are as good as possible according to

the rules

121

slide-123
SLIDE 123

If we want to stick to our simple semantics, with its flavor function (from evaluation worlds to sets of worlds quantified

  • ver), we have to locate the complexity in the pragmatics of

determining a salient value to the context-dependent flavor.

122

slide-124
SLIDE 124

Alternatively, we can complicate the semantics. This is what Kratzer did.

123

slide-125
SLIDE 125
  • In full generality, Kratzer assumes two contextually

supplied parameters.

  • They are both functions from evaluation worlds to sets of

propositions.

  • One is employed as the modal base, to determine for

each evaluation world a set of worlds (= the intersection

  • f the propositions assigned to the evaluation world)
  • The other is employed as the ordering source, to

determine for each evaluation a preference ordering of worlds (the more propositions in the set of propositions assigned to the evaluation world are true in a world, the better that world)

124

slide-126
SLIDE 126

One can imagine systems of intermediate complexity. For example, one could sue something of the same type as our simple flavor as the modal base:

  • a function from worlds to sets of worlds (≈ modal

base/accessibility function) And then, a second ordering parameter:

  • a function from worlds to ordering relations (function

from worlds to ordered pairs of worlds, ≈ ordering source)

  • or a function from worlds to subset selection functions

These are mathematically slightly less complex. You’ll find such setups in some of my papers and lecture notes.

125

slide-127
SLIDE 127

Pedagogically and strategically, I like to start with the simplest plausible system and complicate things only if and when needed.

126

slide-128
SLIDE 128

Two proposals for conditionals:

  • 1. if as a necessity modal

127

slide-129
SLIDE 129

if [f(w)] (p) (q)

  • the antecedent p
  • the modal flavor function f(w)
  • the consequent q

true iff ∀w′ ∈ p ∩ f(w): q(w′) = 1.

128

slide-130
SLIDE 130

Two proposals for conditionals:

  • 1. if as a necessity modal
  • 2. if as a (plural) definite description operator

129

slide-131
SLIDE 131

if f(w) (p) = the plurality of worlds that contains the p-worlds in f(w) if f(w) (p), ∗q true iff q is true of every world in the plurality of worlds denoted by if f(w) (p)

130

slide-132
SLIDE 132
  • 3. Interactions

131

slide-133
SLIDE 133

Semantics is a lab science in several ways. The most crucial way is that we learn a lot about our objects of study when we put them together and see how they react to each other.

132

slide-134
SLIDE 134

Modal sentences, conditional sentences, and their sentential constituents (the prejacent of modals, the antecedent and consequent of conditionals) are all the same type (propositions, functions from worlds to truth-values). So, we expect them to freely mix-and-match, embed in each

  • ther.

133

slide-135
SLIDE 135

Modal sentences in the antecedent of conditionals

134

slide-136
SLIDE 136

No problem: (34) If Howard has to pay a heavy fine, he will be broke. (35) If one can get to that beach by bike, Iris did just that.

135

slide-137
SLIDE 137

Epistemic modals in the antecedent? Lots of people think not. For example, Papafragou 2006: (36) a. ?If Max must be lonely, his wife will be worried. b. ?If Max may be lonely, his wife will be worried.

136

slide-138
SLIDE 138

Conditionals signal that the antecedent is “iffy”. An epistemic modal statement can only be “iffy”, if the speaker is not certain about what “the evidence” is. That can only be if “the evidence” is not the evidence that the speaker has full access to.

137

slide-139
SLIDE 139

(37) If there have to be two reds, your next move is obvious. (38) If John might have cancer [the doctors haven’t told us], he will have to see an expert in Boston.

138

slide-140
SLIDE 140

Modal sentences in the consequent of conditionals

139

slide-141
SLIDE 141

(39) If jaywalking is illegal here, then that guy has to pay a fine.

140

slide-142
SLIDE 142

A scenario devised by Sarah Moss: We’re trying to figure out what the roommate arrangements between Caspar and Chris are. We have concluded that one of them vacuums on Saturdays and the other cooks on Sundays. (40) If Caspar vacuums on Saturday, then Chris has to cook

  • n Sunday.

141

slide-143
SLIDE 143

An example due to Zsofia Zvolenszky: (41) If Britanny drinks Coke, she must drink Coke. If we saw Britanny drink Coke, we would conclude that she’s contractually required to drink Coke.

142

slide-144
SLIDE 144

(42) If Howard returns his book late, he has to pay a fine.

143

slide-145
SLIDE 145

Modals in both components of a conditional: (43) If Cosette has to be home by midnight, she ought to think about leaving now.

144

slide-146
SLIDE 146

So far, so good

145

slide-147
SLIDE 147

Modals and conditionals — Day Four

146

slide-148
SLIDE 148

Our friends Jacy and Macy have been driving in the Massachusetts hinterlands, inexplicably without iPhones or GPS, and are relying entirely on an old-fashioned map. They’ve just passed through a little town with an iconic New England church and are looking on the map to try to figure out where they are. They have concluded that they are either on Route 117 or on Route 62. There are two plausible candidate towns on Route 117 (Maynard and Stow) and just one on Route 62 (Clinton).

147

slide-149
SLIDE 149

148

slide-150
SLIDE 150

They are on Rte 62 (and don’t know it) or on Rte 117 (and don’t know it). They are in Maynard, Stow, or Clinton (and don’t know it).

149

slide-151
SLIDE 151

It’s true when they say: (44) We might be in Maynard. since there are worlds compatible with their evidence where they are in Maynard.

150

slide-152
SLIDE 152

It’s true when they say: (45) If we’re on Route 62, we’re in Clinton. Because of the three towns that they know they might be in,

  • nly Clinton is on Rte 62.

151

slide-153
SLIDE 153

Our semantics for conditionals (either the modal analysis or the plural description analysis) has the conditional take us to worlds that are (i) in f(w), here in the set of worlds compatible with their evidence and (ii) are antecedent worlds. Among the worlds compatible with their evidence, all p-worlds (worlds where they are in Rte 62) are worlds where they are in Clinton.

152

slide-154
SLIDE 154

Problem cases (46) a. If we’re on Route 117, we might be in Stow.

True

b. If we’re on Route 117, we might be in Clinton.

False

c. If we’re on Route 62, we must be in Clinton.

True

These cannot be explained in our framework!

153

slide-155
SLIDE 155

Take (47) If we’re on Route 62, we must be in Clinton. The conditional takes us to those worlds that are (i) compatible with their evidence, with what they know (which includes their knowledge that they don’t know in which of the three towns they are) and (ii) where they are on Rte 62. In all of those worlds, they are in Clinton, but in none of them do they know or have any additional evidence that they are in Clinton.

154

slide-156
SLIDE 156

Some of the ways out:

  • 1. The Restrictor Theory
  • 2. A non-epistemic analysis of epistemic modals
  • 3. A meaning for conditionals where “if p” means “if we

learn p” [… surely more, we’re desperate after all]

155

slide-157
SLIDE 157

We’ll leave the idea that epistemic modals are not epistemic

  • aside. It’s been pursued:
  • Yalcin 2007 (“Epistemic modals”, Mind)
  • Gillies 2010 (“Iffiness”, S&P)

156

slide-158
SLIDE 158

We’ll also leave the idea aside that “if p” doesn’t mean “if p” but “if we learn p”. It’s been pursued (in a related context):

  • von Fintel 2012 (“The best we can (expect to) get?

Challenges to the classic semantics for deontic modals”)

157

slide-159
SLIDE 159

The Restrictor Theory

158

slide-160
SLIDE 160

Kratzer 1986: the history of the conditional is the story of a syntactic mistake. There is no two-place if …then connective in the logical forms of natural languages. If-clauses are devices for restricting the domains of various operators.

159

slide-161
SLIDE 161

Kratzer’s Thesis If-clauses are devices for restricting the domains of various

  • perators.

160

slide-162
SLIDE 162

(48) If we’re on Route 62, we must be in Clinton. must [f(w) ∩ p] (we be in Clinton) The only thing the if-clause is doing is restricting the flavor argument of must. There’s no additional modal operator contributed by if.

161

slide-163
SLIDE 163

What now about the modal-less conditional? (49) If we’re on Route 62, we are in Clinton. If if is a device for restricting the domains of operators, where is the operator being restricted here?

162

slide-164
SLIDE 164

Two options:

  • if ambiguous between modal operator and restrictor

readings

  • if always a restrictor, “bare” conditionals have covert

modals Kratzer: covert modals

163

slide-165
SLIDE 165

Some questions:

  • 1. Can the restrictor theory cover all the cases that

previously we viewed as involving nested modality (conditional on top of a modal)?

  • 2. Can we finally decide whether we can have a theory with a

simple flavor function, or do we need the Kratzerian two-parameter theory?

164

slide-166
SLIDE 166

(50) If Howard returned his book late, he has to pay a fine.

165

slide-167
SLIDE 167

Earlier, this seemed unremarkable:

  • we don’t know if Howard returned his book late
  • but in the worlds compatible with our evidence where he

did, the rules are such that in such a circumstance they require a fine How does the restrictor theory deal with this case?

166

slide-168
SLIDE 168

Assume the simple flavor view: The consequent modal has a flavor argument f(w) and the if p-clause is used to restrict that to the p worlds in f(w). λw. M [f(w) ∩ p] (q)

167

slide-169
SLIDE 169

In our case (Howard has to pay a fine), f(w) is a complex flavor (combining the actual circumstances and what the rules say about those circumstances)

168

slide-170
SLIDE 170

Imagine that unbeknownst to us Howard did return his book

  • n time.

169

slide-171
SLIDE 171

Now, we say (51) If Howard returned his book late, he has to pay a fine. It seems we’re saying something true (even though in actual fact, he returned his book on time).

170

slide-172
SLIDE 172

The simple view does not get that right. λw. M [f(w) ∩ p] (q)

  • f(w) contains only worlds where the circumstances are like

in the actual world, including that Howard returned his book on time, and in none of those does he pay a fine

  • if f(w) contained all the best worlds compatible with our

evidence (we don’t know whether he returned the book on time), the best worlds will still be worlds where he did return the book on time and doesn’t pay a fine

  • in either case, when we intersect that set with the

proposition that he returned the book late, we get the empty set

171

slide-173
SLIDE 173
  • ⇒ under the restrictor theory the simple view is wrong:

complex flavors need a complex representation.

  • the restrictive if-clause restricts only the modal base

(which has to be epistemic in our case)

  • the ordering happens on top of that

λw. M (O(w)[M(w) ∩ p]) (q)

172

slide-174
SLIDE 174

A problem

173

slide-175
SLIDE 175

Zvolenszky’s example again: (52) If Britanny drinks Coke, she has to drink Coke. If the if-clause restricts the modal base to worlds where Britanny drinks Coke, then it is trivially true that the best worlds among those are worlds where she drinks Coke.

174

slide-176
SLIDE 176

The way out for the restrictor theory

175

slide-177
SLIDE 177

In the restrictor theory, conditionals with modals in the consequent are in principle structurally ambiguous:

  • if restricts the overt modal
  • if restricts a covert modal that takes the overt modal as

its argument.

176

slide-178
SLIDE 178

(53) If Britanny drinks Coke, she has to drink Coke. ≈ (54) If Britanny drinks Coke, she must have to drink Coke.

177

slide-179
SLIDE 179

Once we recognize the availability of nested structures (covert modal restricted by if + overt modal embedded in the consequent), we see that the restrictor theory can mimic our previous theory in all cases where it was successful.

178

slide-180
SLIDE 180

(55) If jaywalking is illegal here, then that guy has to pay a fine. (56) If Cosette has to be home by midnight, she ought to think about leaving now.

179

slide-181
SLIDE 181

Anette Frank 1997: “There are in fact no truly deontically modalized if-conditionals. Instead, we assume conditionals with a deontic modal operator in the consequent clause to be analyzed throughout in terms of an implicit or explicit epistemically (or circumstantially) based modal operator. The deontic modal adverb is then to be analyzed within the scope

  • f the ‘higher’ epistemic modal operator.”

180

slide-182
SLIDE 182

We have to revisit our earlier conclusion that the simple flavor view is not compatible with the restrictor theory.

181

slide-183
SLIDE 183

(57) If Howard returned his book late, he has to pay a fine. This can be analyzed as a nested structure with a simple flavor analysis.

182

slide-184
SLIDE 184

What would it take to show that we need a non-nested complex representation of a conditional with a complex-flavor modal in the consequent?

183

slide-185
SLIDE 185

Add to our Massachusetts scenario, that there are two Route 62 possibilities, one is Clinton (which is much more likely) and the other, quite unlikely, is Berlin. (58) If we’re on Rte 62, we ought to be in Clinton.

184

slide-186
SLIDE 186

Epistemic modals provide the strongest arguments for both the restrictor theory and the complex analysis of complex flavors.

185

slide-187
SLIDE 187

What could be next if we had more time together:

  • anankastic conditionals (another case for nested

structures)

  • adverbs of quantification and the restrictor theory
  • the non-epistemic analysis of epistemic modals
  • information-sensitive deontic modals (the “Miners

Paradox”)

  • the “indicative”/“subjunctive” distinction in modals &

conditionals

  • the cross-linguistics of weak necessity

186

slide-188
SLIDE 188

Ask me anything

187

slide-189
SLIDE 189

Bonus section: The referential view

188

slide-190
SLIDE 190

Is the restrictor theory compatible with the idea that if-clauses are definite descriptions of pluralities of worlds?

189

slide-191
SLIDE 191

Simple case: if f(w) (p), * q No covert modal needed. The work is distributed between the f(w) flavor argument of if and the star-operator.

190

slide-192
SLIDE 192

Nested reading: if f(w) (p), * λw’. M f’(w’) q

191

slide-193
SLIDE 193

But what about the one-modal restricted reading (like the examples with our lost friends)? That must be analyzed without the star-operator. But how?

192

slide-194
SLIDE 194

if f(w) (p), λP M P q

193

slide-195
SLIDE 195

End of Bonus section

194