Factibilidad técnica del proyecto

As stated in §(2.1.1), it is commonly held that a constituent within an occurrence of a sen- tence is part of the sentence’sfocus when the understanding of the sentence partially de- pends on the availability of certain alternatives to that lexical item. The standard way of

formalising the role of focus as an indicator of alternatives is by means of the system ofAl- ternative Semanticsdeveloped in Rooth (1985), Kratzer (1991) and Rooth (1992). Alternative Semantics defines thefocus semantic valueof an occurrence of a sentence as ‘the set of propo- sitions obtainable from the ordinary semantic value by making a substitution in the position corresponding to the focused phrase ... At an intuitive level, we think of the focus semantic value of a sentence as a set of alternatives from which the ordinary semantic value is drawn, or a set of propositions which potentially contrast with the ordinary semantic value’.35 More technically, an occurrence of an expressionα relative to a CGcis assigned afocus semantic valueJαK

f

c in addition to itsordinary semantic valueJαK

o

c. The focus semantic value is a set of

items of the same type as the item denoted byα, which is derived fromα’s ordinary semantic value by inserting an appropriately-typed free variable in the position corresponding to the focus ofα. The type constraints for the free variable are imposed by specifying the domain that its value must belong to. In addition to the basic domainsDe andDt (respectively of

individuals and propositions), complex domainsDhσ,τiare defined as sets of functions from Dσ toDτ, where bothσandτ are well-formed semantic types.36 Rooth (1985) furthermore

gives a recursive definition of focus value, therefore assigning such values to sub-sentential constituents.

For example, where ‘[]F’ indicates the constituent in focus, the focus value of (7a) will

be the set of propositions expressed by sentences of the form ‘YX is bald’ (e.g. ‘Some king is bald’, ‘No cat is bald’, ‘Every tree is bald’, etc.), and the focus value of (7b) will be the set of propositions expressed by sentences of the form ‘Some kingX’ (e.g. ‘Some king is bald’, ‘Some king is outside’, ‘Some king is a cat’, etc.):

7. (a) J[Some king]F is baldK

f

c ={JY(X)(is bald)K

o c|JYK

o

c ∈Dhhe,ti,hhe,ti,tii&JXK

o

c∈Dhe,ti}

(b) JSome king [is bald]FK

f c ={JSome (king)(X)K o c|JXK o c∈Dhe,ti}

Having sketched the standard analysis of focus as a means of indicating alternatives relevant to understanding an occurrence of a sentence, we may now turn to the matter of recognising the focus of an occurrence of a sentence. For most sentences, occurrences with distinct choices of focus are possible. However, the prosody, communicative needs and syn- tactic structure associated with an occurrence of a sentence will constrain the focus choice that may be attributed to that occurrence. Firstly, with respect toprosody, it is widely ac- cepted that focus is identified in spoken English viapitch accent, which is a ‘local maximum or minimum of the fundamental frequency’, indicated by capitalisation in written form.37 B ¨uring (2016) (pp.6-7) claims thatneutral prosodyfor an English sentence involves the assign- ment of pitch accents to the minimal number ofopen class elements(i.e. nouns, adjectives and

35_{Rooth (1992), p.76.} 36_WhileD

t is usually treated as a domain of truth values, it is important for the focus semantic values of

occurrences of sentences to end up as a set of propositions (construed as sets of contexts of evaluation) rather than a set of truth values. While this could be implemented by recursively defining the intensions of expressions (as in Rooth (1985)), a simpler approach achieves the same effect by interpreting occurrences of sentences in a domain of propositions. The ordinary semantic value of a sentence ‘α(β)’ would therefore be accurately represented asJλi.[α(i)(β(i))]K

o

c, in order to reflect its status as a function from contexts of evaluationito the

extension of each constituent ati. However, I will omit lambda abstraction over contexts of evaluation variables when writing such interpretations, for simplicity.

main verbs) such that each syntactic phrase contains at least one pitch accent; optional rules then allow accents to be removed from or added to open class elements preceding the ex- pression that receives the clause-final pitch accent. The effect of focus assignment on neutral prosody is generally accepted to include the following: the lexical material in a focus must carry at least one pitch accent, and the item on which the clause-final pitch accent falls is obli- gatorily included in the focus. However, there is debate about the correct rules governing exactly which items within a focus must receive a pitch accent.Restrictedviews of focus pro- jection (e.g. Gussenhoven (1983), Ladd, Fuchs (1984), Baart (1987) and Gussenhoven (1999)) hold that it is possible for a clause to be in focus only if pitch accents occur on at least every argument and modifier that precedes the final accented word, whereasextendedviews (e.g. Chomsky (1971), Jackendoff (1972), Steedman (1994) and B ¨uring (2016)) frequently allow a single accented word to ‘project’ focus to an entire complex clause. Given that everything to follow is compatible with any pairing of focus choice and prosodic structure that conforms with the generally accepted effects of focus assignment on neutral prosody, I shall not enter into this debate.38

A second crucial factor that constrains focus choice consists ofcommunicative needs. More specifically, an occurrence of a sentence provides a felicitous answer to a QUD only if it is congruent with that QUD by virtue of having a suitable focus. The intuitive explanation for the congruence required between a question and an occurrence that provides an answer derives from the role of focus as an indicator of alternatives, insofar as focus serves to ‘signal other propositions which are potential answers in the context of the question’.39 If we use the system of Alternative Semantics earlier described, along with Hamblin’s semantics for questions, then it is possible to give a precise statement of this congruence between QUDs and their answers:40

Question-Answer Congruence principle: An occurrence s of a sentence relative to a CGciscongruentwith the meaning of a question q iff:

a)JqK

o c⊆JsK

f c, and

b) There is no alternative occurrence s0 of s which has a smaller constituent in focus and meets a).

A question q may be morespecificthan some s that provides a felicitous answer, which is the case whenever its meaning is a proper subset of the focus value of s. This reflects the fact that questions sometimes include information that cannot be reconstructed from the focus value of an occurrence of a sentence congruent with the question’s meaning. For example,

38_{It is worth noting that the data seems to support restricted views. Gussenhoven (1999) (p.46.) gives the}

following example, where (a) is an appropriate answer to the question ‘What’s happening?’ (thereby having sentence-wide focus) while (b) may only appropriately answer the question ‘What’s John tickling Mary with?’ (thereby having narrow focus on ‘a feather’)

(a) JOHN’s tickling MARY with a FEATHer. (b) John’s tickling Mary with a FEATHer.

Extended views predict that (b) is an appropriate answer to ‘What’s happening?’; my judgement accords with Gussenhoven’s that this prediction is incorrect.

39_{Rooth (1992), p.84.} 40_{B ¨uring (2007), p.451.}

when the ‘wh’-word ‘who’ is used in a question, the free variable in its ordinary meaning is restricted to a domain composed of human individuals, whereas the free variable in the focus value of an answer need not include such a restriction.41 The reason there cannot be an alternative occurrence of the sentence with a smaller constituent in focus is to rule out situations where s0 counts as congruent with the meaning of q by virtue of having an arbitrarily large constituent in focus that contains the smaller constituent that would yield the correct focus value. For instance, an occurrence of ‘[Zaid uprooted everything in his yard]F’ should not count as congruent with the meaning of the question ‘Who uprooted

everything in his yard?’.

In light of this discussion, it should be clear that the link between prosody, communica- tive needs and focus is extremely direct. That is, intoning a sentence with particular pitch accents restricts the possible choices of focus, and intending to convey a certain choice of focus restricts the possible placement of pitch accents. Similarly, we can either infer the re- quired focus for an occurrence of a sentence that provides a felicitous answer to a particular explicit QUD, or reconstruct the implicit QUD in light of a particular occurrence of a sen- tence. Indeed, in cases where the QUD is implicit, the foci of occurrences of sentences will not only allow the reconstruction of the congruent QUD, but they willpresupposea particular QUD.

A third factor,syntactic structure, has also been observed to constrain focus choice; how- ever, its effect is arguably restricted to cases where neither prosody nor communicative needs are present to provide clues as to the choice of focus. Such cases arise for out-of- contextsentences, where the way in which a speaker should intone the sentence is not in- dicated, and no background context is described that is sufficiently rich to provide crucial features of a CG such as a QUD. It is reasonable to deny that individuals ever assign in- terpretations to context-independent sentence types. I shall therefore endorse the idea that assessors who encounter an out-of-context sentence will assess an occurrence of it relative to an imaginedminimal context, by which I mean a context that associates a prosodic structure with a sentence along with a QUD corresponding to the resulting focus value. Evidence for this claim derives from experimental data given by Tian and Breheny (2015), which they take to show that we infer contextual information and accommodate QUDs ‘when we en- gage in conversation,andwhen we read speakerless out-of-context sentences ... Sentence comprehension can never be independent from context’.42 _{Furthermore, work on implicit}

prosody (Fodor (1998), Bader (1998), Quinn et al. (2000), Fodor (2002)) indicates that asses- sors assign a prosodic contour to out-of-context sentences they encounter even under a silent reading, generally assigning ‘the most natural (default) prosodic contour for the construc- tion’.43 Given the connection between prosody, QUDs and focus, it follows that individuals assign out-of-context sentences a particular focus choice. Furthermore, given the preference for attributing to out-of-context sentences the prosody most natural for the relevant gram- matical construction, it follows that the syntactic structure of such sentences influences the foci assessors are likely to assign to them.

In summary, I have characterised the IS-theoretic notion of focus as an indicator of al- ternatives relevant to understanding, and explained how focus choice is constrained by

41_{Rooth (1992), pp.85-6.} 42_{Tian and Breheny (2015), p.28.} 43_{Fodor (2002), p.113.}

prosody, communicative needs and syntactic structure. In the following subsection, I shall explore the empirical connections between the focus and the topic of an occurrence of a sentence, raising the possibility of using the hallmarks of focus to identify topic.