A Semantics and Pragmatics for the Pluperfect 
Alex Lascarides* 
Centre for Cognitive Science and 
Human Communication Research Centre 
University of Edinburgh 
2, Buccleuch Place 
Edinburgh EH8 9LW, Scotland, UK 
alexl~k, ac. ed. copci 
Nicholas Asher 
IRIT, Umvermt~ Paul Sabatier 
118 Route de Narboane 
31062 Toulouse Cedex, France 
also at: Centre for Cognitive Science and 
Department of philosophy 
University of Texas, Austin 
asherlirit .it 
Abstract 
We offer a semantics and pragmatics of the 
pluperfect in narrative discourse. We rex- 
amine in a formal model of implicature, 
how the reader's knowledge about the dis- 
course, Gricean-maxims and causation con- 
tribute to the meaning of the pluperfect. 
By placing the analysis in a theory where 
the interactions among these knowledge re- 
sources can be precisely computed, we over- 
come some problems with previous Re- 
ichenbachian approaches. 
1 Introduction 
In this paper, we investigate the impact of the plu- 
perfect tense on the temporal and rhetorical struc- 
ture of narrative discourse. We will use a represen- 
tation framework for discourse structure called SDRT 
(standing for Segmented Discourse Representation 
Theory) (Asher 1993), and a theory of discourse at- 
tachment called DICE (standing for Discourse and 
Commonsense Entailment), which is designed to 
compute temporal implicatures for natural language 
texts (Lascarides and Asher 1991). We will argue 
that the resultant analysis overcomes problems with 
Reichenbachian theories of tense (e.g., Kamp 1991a). 
2 Limitations of Kamp's Account 
Kamp's (1991a) Reichenbachian account of the plu- 
perfect is problematic in at least three ways. Firstly, 
the temporal structure of a text is determined solely 
*The support of the Science and Engineering Research 
Council through project number GR/G22077 is grate- 
fully acknowledged. HCRC is supported by the Economic 
and Social Research Council. 
from syntax, so there can be no explanation of why 
even though (1) has the same tense structure as (2), 
they are interpreted differently: no order is inferred 
between the events in (1b-d) while there is temporal 
progression in (2b-d). 
(1) a. Alexis was a very good girl by the time 
she went to bed yesterday. 
b. She had helped her mum withthe house- 
work. 
c. She had practised her piano. 
d. She had done all her homework. 
e. We all felt very good about it. 
(2) a. Max arrived at the summit at midday. 
b. He had got up at 5:30am, 
c. had prepared his lunch, and 
d. had passed base camp before 7am. 
Intuitively, the order of events in (2b-d) is inferred 
from causal knowledge about the typical orders be- 
tween the events and by the temporal information 
conveyed by the list structure. In contrast, there is 
no knowledge that enables such an inference in (lb- 
d). An explanation in these terms requires us to 
solve the Interaction Problem: The anMysis of the 
pluperfect must interact in precise and systematic 
ways with the reader's causal knowledge, pragmatic 
maxims and the discourse type to yield appropri- 
ate temporal structures. Kamp's syntactic-based ac- 
count fails to specify such interactions. 
The second problem is that, in line with the Re- 
ichenbachian approach, the semantics of tense ap- 
peals only to temporal relations. But consider texts 
(3) to (5). 
(3) Max entered the room. He poured himself a 
cup of coffee. 
250 
(4) ?Max poured himself a cup of coffee. He had 
entered the room. 
(5) Max poured himself a cup of coffee. He had 
entered the room feeling depressed, but now 
he felt much better. 
Texts (3) and (4) attempt to describe similar tem- 
poral relations, and yet only (3) is acceptable. Simi- 
larly, (4) and (5) describe similar temporal relations 
between the first event mentioned and the second, 
but only (5) is acceptable. One can view (3) to (5) 
as a manifestation of contextual relevance; a similar 
view is proposed in Caenepeel and SandstrSm (1992). 
One event being in the consequent state of the other 
is sufficient for simple past tensed text to satisfy the 
Contextual Relevance Constraint (eft (3)), but it 
won't do for the pluperfect in (4), although the ad- 
ditional information in (5) ameliorates (4)'s incoher- 
ence. We can thus think of the pluperfect as a dis- 
course marker that indicates that the range of possi- 
ble connections that would make the clause 'contex- 
tually relevant' is restricted (relative to the possibil- 
ities for the simple past). This yields the Relevance 
Problem: The analysis of the pluperfect must take 
Contextual Relevance into account. Kamp (1991a) 
fails to explain the incoherence of (4) because the Re- 
ichenbachian analysis doesn't solve this problem: to 
solve it, a Reiehenbachian semantics of tense would 
have to be extended so that it considers causal and 
rhetorical connections, as well as temporal relations. 
A third problem with the Reichenbachian account 
of tense is that the purely temporal specification fails 
to explain why the pluperfect clause can initiate a 
perspective shift such as those that occur in free in- 
direct style, where the control over the proposition 
shifts from the author to a character in the text 
(Leech and Short 1981, Quirk et al. 1985). For ex- 
ample, consider text (6), taken from Nakhimovsky 
(1988): 
(6) a. The telephone rang. 
b. It was Mme Dupont. 
c. Her husband had eaten too many oysters 
for lunch. 
d. The doctor recommended a change in 
lifestyle 
(6c) initiates free indirect style: Control over the 
proposition in (6c) is shifted from the author to Mme 
Dupont, because in contrast to (6b), (6c) reports 
Mine Dupont's perceptions (of what was said over 
the phone). The pluperfect plays a crucial role in 
creating free indirect style in (6), for replacing it with 
the simple past would mean that the author's per- 
spective is maintained: 
(6) d. Her husband ate too many oysters for 
lunch. 
This yields the Perspective Problem: The semantic 
framework used must be able to represent perspec- 
tive, such as those that occur in indirect speech. Al- 
though Discourse Representation Theory (DRT) is a 
rich semantic framework in which perspective can be 
represented, the analysis of tense in DgT presented 
in (Kamp 1991a) fails to exploit this. All purely Re- 
ichenbachian treatments of tense fail to capture shifts 
in perspective, because they don't take into account 
the information status of the clauses concerned. 
In order to solve the Interaction, Relevance and 
Perspective Problems, we will formalise the discourse 
role of the pluperfect using two tools: a semantically- 
based theory of discourse structure called SVgT, and 
a formal theory of discourse attachment called DICE. 
Using these tools, we model both the pluperfect's se- 
mantic and pragmatic contributions to discourse. In 
contrast to Kamp (1991a), we will examine the role 
that the reader's background knowledge plays in in- 
terpreting the pluperfect tense, and provide analy- 
ses of the above texts. The reason we devote atten- 
tion to a formal account is because we assume that 
the reader's various knowledge resources on occasion 
yield conflicting conclusions about discourse struc- 
ture (cf. Hobbs 1985, Lascarides and Asher 1991), 
and resolving the conflicts is arbitrary unless sup- 
ported by an underlying logical consequence relation. 
3 A Description of SDRT and DICE 
We start with a brief overview of SDRT and DICE. 
SDRT (Asher 1993) takes the basic building blocks 
of discourse structure to be propositions with a dy- 
namic content, which are represented as DaSs--the 
representation scheme in Kamp's (1981) DRT. How- 
ever, discourse relations may also obtain between 
more complex structures---segmented DRSs (SDgSs), 
which are defined recursively. In SDRT, an NL text 
is represented by an SDRS, which is a pair of sets 
containing respectively: the DgSs or SDgSS repre- 
senting respectively sentences or text segments, and 
discourse relations between them. These structures 
are constructed in a dynamic, incremental fashion. 
The default assumption is that the sentence bound- 
ary marks the unit of information to be attached to 
the SDRS for the preceding discourse. 
Discourse relations modelled after those proposed 
by Hobbs (1985) and Thompson and Mann (1987) 
link together the constituents of an SDRS. We will 
use seven discourse relations: Narration, Elabora- 
tion, Explanation, Background, Continuation, Par- 
allel and Contrast. The first four of these constrain 
temporal structure: Narration entails that the de- 
scriptive order of events matches their temporal or- 
der; an Explanation or Elaboration entail they mis- 
match; and Background entails temporal overlap. 
The recursive nature of SDRSs gives discourse 
structures a hierarchical configuration. Certain dis- 
course relations in an SDRS impose a hierarchical 
structure; these subordinating relations are Elabo- 
ration and Explanation. The so-called open con- 
stituents to which new information can attach are 
the previous constituent or constituents it elaborates 
or explains. Thus the open clauses are those on the 
251 
right frontier of the discourse structure (cf. Polanyi 
1985, Grosz and Sidner 1986, Webber 1991), assum- 
ing that it is built in a depth first left to right manner. 
SDRT specifies which parts of the SDRS are avail- 
able to the representation of the current sentence for 
attachment via a discourse relation. DICE provides 
the means to infer from the reader's knowledge re- 
sources which discourse relation should be used to do 
attachment. DICE makes the following claims. The 
current sentence is attached to the preceding SDRS 
with a discourse relation; the process by which this 
is done takes the reader's background knowledge into 
account, and the resulting SDRS determines how time 
is structured in the discourse. Here, we assume the 
reader's knowledge base (KB) contains: the SDRS for 
the text so far; the logical form of the current sen- 
tence; an assumption that that logical form must 
attach at an open site (i.e., the text is coherent); 
all defeasible and indefeasible world and pragmatic 
knowledge; and the laws of logic. 
The rules introduced below are shown in Las- 
carides and Asher (1991) to be manifestations of 
Gricean-style pragmatic maxims and world knowl- 
edge; we assume they form part of the reader's KB. 
A formal notation makes clear both the logical struc- 
ture of these rules, and the problems involved in 
calculating implicature. Let (% a,/3) be the update 
function, which means "the representation v of the 
text so far, of which c~ is an open node, is to be up- 
dated with the representation/3 of the current sen- 
tence via a discourse relation with a". Let a 4~/3 
mean that a is a topic for/3; let ea be a term refer- 
ring to the main eventuality described by the clause 
a; and let fall(m, ea) mean that this event is a Max 
falling. Let el -4 e2 mean the eventuality el precedes 
e2, and cause(el, e2) mean £1 causes e2. Finally, we 
represent the defeasible connective as a conditional > 
(so ~ > ~b means 'if ql, then normally ~b'). The max- 
ims for modelling implicature are then represented 
as schemas: 
• Naxration: (% a, 13) > Narration(a,/3) 
• Axiom on llaxration:  (Ua  ation(a,/3) 
• States Overlap: 
(r, a,/3) A state(e#) > overlap(e,, e#) 
• Background: 
(,', a,/3) A overlap( e~ , eo ) > Background(a,/3) 
• Axiom on Background: 
iT(Background(a,/3) -+ overlap( e~ , ea ) ) 
• Continuation: 
(r,/3, 7) A a .\[J./3 > Continuation(~3, 7) 
• Continuing Discourse Patterns: 
D((r, a, 7)Aa 4~/3A ~b(o~,/3) A Continuation(~3, 7) 
-- v)) 
• Causes Precede Effects: 
D(cause(e2, el) ~ -~el -~ e2) 
The rules for Narration and its Axiom convey in- 
formation about the pragmatic effects of the tex- 
tual order of events; by default, textual order mir- 
rors temporal order. States Overlap, Background 
and its Axiom convey the pragmatic effects derived 
from aktionsart information (states normally provide 
background information). Continuation and Contin- 
uing Discourse Patterns convey the pragmatic effects 
of the preceding discourse structure; they state that 
normally, the current clause 7 continues to describe 
the same topic a as the preceding clause/3 did (for 
in SDRT, Continuation(~3, 7) entails/3 and 7 have the 
same topic a), and 7 is related to a by the same dis- 
course relation. Finally, that Causes Precede their 
Effects is indefeasible world knowledge. 
The logic on which DICE rests is Asher and Mor- 
reau's (1991) Commonsense Entailment (CE). Three 
patterns of nonmonotonic inference are particularly 
relevant. The first is Defeasible Modus Ponens: if 
one default rule has its antecedent verified, then the 
consequent is nonmonotonicaily inferred. The sec- 
ond is the Penguin Principle: if there are conflicting 
default rules that apply, and their antecedents are 
in logical entailment relations, then the consequent 
of the rule with the most specific antecedent is in- 
ferred. The third is the Nixon Diamond: if there are 
conflicting default rules that apply but no logical re- 
lations between the antecedents, then no conclusions 
are inferred. 
In interpreting text (7), the KB contains (a, a,/3), 
where a and/3 are respectively the logical forms of 
the first and second sentences. 
(7) Max stood up. John greeted him. 
(8) Max opened the door. The room was pitch 
dark. 
The only rule that applies is Narration, and its con- 
sequent is inferred via Defeasible Modus Ponens. 
Hence by logical omniscience, the standing up pre- 
cedes the greeting. In contrast, text (8) verifies the 
antecedents to two conflicting defeasible laws: Nar- 
ration and States Overlap. By the Penguin Prin- 
ciple, States Overlap wins, because its antecedent 
logically entails Narration's. In turn, this entails 
that the antecedent to Background is verified; and 
whilst conflicting with Narration, it's more specific, 
and hence its consequent--Background--follows by 
the Penguin Principle. We call this double applica- 
tion of the Penguin Principle the Cascaded Penguin 
Principle. 1 
The Nixon Diamond provides the key to text inco- 
herence (Lascarides and Asher, 1991). If the reader's 
knowledge resources are in irresolvable conflict, no 
1The formal details of how the logic CE models these 
interpretations axe given in Lascaxides and Asher (in 
press). Although the Cascaded Penguin Principle, as in 
(8), is not valid in general, they show that for the partic- 
ular case considered here, CE validates it. 
252 
conclusions about the discourse structure can be in- 
ferred. DICE exploits this account of incoherence in 
its approach to discourse popping. When a Nixon 
Diamond occurs in attempting to attach the current 
clause to the previous one, they don't form a coher- 
ent text segment. So the current clause must attach 
to one of the other open clauses, resulting in dis- 
course popping. 
4 The Semantics of the Pluperfect 
DICE represents temporal information in two places: 
first, in the DRS representing a sentence; and second, 
in the discourse relations. Because of these two lev- 
els, we can preserve sentential equivalence between 
the simple past and pluperfect, while still maintain- 
ing that these tenses play different roles in discourse, 
by ensuring that different default rules for discourse 
attachment apply. We pursue such an analysis of 
the pluperfect here, because in contrast to Hamann 
(1989), it enables us to provide a uniform semantics 
of tense which explains why the simple past and plu- 
perfect are equivalent in sentences containing tempo- 
ral connectives, but different in discourse (see Las- 
caxides and Asher 1992). 
The logical forms of (9) and (10) are respectively 
(9') and (10'). 
(9) John greeted Max 
e,t 
greet(j, m, e) (9') 
hold(e,t) 
t ..< now 
(10) John had greeted Max 
s,t 
(10') \[ s = cs(e) 
hold(s, t) 
t -4 now 
In (9~), the discourse referent e is a John greeting 
Max event, which holds at the time t preceding now. 
In (10~), s is the consequent state of the event of 
John greeting Max, and it holds at the time t which 
precedes now. So our semantics of the perfect is like 
that in Moens and Steedman (1988): a perfect trans- 
forms an event into a consequent state, and asserts 
that the consequent state holds. The pluperfect of 
a state, such as (11), therefore, is assumed to first 
undergo a transformation into an event. 
(11) John had loved Mary. 
The event is usually the inceptive reading of the 
state in this case, John started to love Mary-- 
although this can vary with the context. Then, the 
pluperfect asserts that the consequent state of this 
event holds--in this case, the consequent state is the 
state of John loving Mary itself. 
We forego defining the function cs which takes 
events to consequent states here for reasons of space, 
but see Lascaxides (1988) and Blackburn and Las- 
caxides (1992) for a proposed semantics. We do, how- 
ever, assume that the following relationship holds be- 
tween an event and its consequent state: 
• Consequent States: 
ra(Vt)( hold(cs(e), t) ~ (3t')( hold(e, t') A t' -4 t) ) 
m(¥t')( hoid( e, t') ~ (3t )(hold( cs( e ), t) ^ t' -< t ) ) 
So a consequent state holds if and only if the event 
holds at an earlier time. This relationship means 
that (9') and (10') are truth conditionally equivalent, 
under the usual assumption that time is dense. They 
only differ in terms of which eventualities are avail- 
able for future anaphoric reference. This equivalence 
is in sharp contrast to all Reichenbachian treatments 
of the tenses. 
The main eventuality in (10) is the consequent 
state s of John having greeted Max. But sometimes 
in discourse attachment it is useful to refer in the 
rules of attachment to the event of John greeting 
Max itself, which is embedded in (10'). To do this, 
we define a function ev on eventualities: 
ev(e) = { e' if e = cs(e') 
e otherwise 
5 The Pragmatics of the Pluperfect 
We now show how the discourse role of the pluperfect 
can be captured. We argued earlier that the range 
of possibilities for connecting a pluperfect clause to 
a simple past tensed one is smaller than the range 
of possibilities allowed for connecting a simple past 
tensed clause to a simple past tensed one (cf. (3) vs. 
(4)). We will show that to account for the above 
data, the discourse relations permitted between a 
simple past and pluperfect are exactly Elaboration, 
Explanation, Parallel and Contrast. This would be 
what one would intuitively expect, for these are the 
only discourse relations we consider that are compat- 
ible with a backwards movement of time in discourse, 
and the pluperfect in general indicates this temporal 
structure. 
We represent this constraint as defeasible knowl- 
edge, for (12) is an exception: 
• Constraint When Changing Tense (CCT): 
(r, c~, fl) A sp(cr) A pp(/3) > Cpp(a, fl) 
(12) Max left the house at 7am. He had passed 
the station by 9:lSam. 
CCT states that. if a pluperfect clause /3 is to be at- 
tached to a simple past tensed clause a, then the 
discourse relation between them must be defined by 
Cry, which is the condition that the consequent state 
described in the pluperfect must include the eventu- 
ality described in the simple past, and furthermore. 
one of Elaboration, Explanation, Parallel and Con- 
trast must hold. Elaboration and Explanation im- 
pose a backwards movement of time in discourse by 
253 
their semantics. The temporal condition of inclusion 
imposed by Cpp ensures that, if the discourse rela- 
tion between a stative simple past sentence and the 
pluperfect one is Parallelor Contrast, then the back- 
wards movement of time between the eventualities 
described still holds, as we will see shortly. 
5.1 A Simple ExAmple 
First we consider CCT'S impact on text (13), and 
contrast this with VlCV.'s analysis of text (7). 
(13) Max stood up. John had greeted him. 
In the interpretationof (13), the rules that apply are: 
Narration, States Overlap and CCT. By the Pen- 
guin Principle, one infers that the consequent state 
of greeting and standing up overlap (by States Over- 
lap), and that the clauses are related by Cpp. In addi- 
tion, the Greeting Law below captures the intuition 
that if a standing up and a greeting are connected, 
and moreover, we know that the connection is Cpp, 
then in the absence of information to the contrary, 
the relation Explanation is preferred in that context 
(for out of the four choices, John's greeting Max ex- 
plaining why Max stood up is the most plausible). 
• 6reefing Law: 
( ( r, a,/3) A standup( ev( ea ) ) A greeting( ev( e# ) ) A 
c.(a./3)) > En.tanation(a./3) 
Now Background and the Greeting Law apply, and 
one infers Background(a,/3) and Explanation(a,/3).2 
So the consequent state of the greeting is in force 
when Max stands up, and the greeting explains why 
Max stood up. Thus CCT helps us model the differ- 
ence between (7) and (13). 
CCT overcomes a flaw in the semantics of the plu- 
perfect presented in (Lascarides and Asher in press); 
there, the constraint was presented as indefeasible, 
and consequently was unable to explain (12). Mak- 
ing CCT defeasible has also changed the inference 
pattern underlying the analysis of (13). Whereas in 
Lascarides and Asher (in press) Cpp(a,/3) is inferred 
monotonically from the premises by modus ponens; 
here, the inference pattern is the Penguin Principle. 
5.2 An Example of Incoherence 
Now consider texts (3) and (4); we infer that the 
discourse relation connecting the sentences in (3) is 
Narration. 
(3) Max entered the room. He poured himself a 
cup of coffee. 
(4) ?Max poured himself a cup of coffee. He had 
entered the room. 
The laws that apply in the analysis of (4) are Nar- 
ration, States Overlap and COT. As in the analysis 
of (13), overlap(ea,e#) and Cpp(a,/3) are inferred. 
However, our knowledge about pouring coffee and 
2As in the Cascaded Penguin Principle, we can divide 
up the nonmonotonic reasoning in this way in this case. 
entering a room means that we don't have a law like 
the Greeting Law which allows us to infer which re- 
lation permitted by Cpp is most plausible. So we 
fail to infer which of the four permitted discourse 
relations holds for (4). And we assume that know- 
ing one of a set of discourse relations must hold, but 
not being able to infer which actually holds, is suffi- 
cient grounds for incoherence. The Nixon Diamond 
mentioned earlier, which leads to incoherence, is a 
specific case of this. 
Now consider text (5). 
(5) Max poured himself a cup of coffee. He had 
entered the room feeling depressed, but now 
he felt much better. 
The default assumption in DICE is that one con- 
structs the DRSS for whole sentences before one at- 
tempts discourse attachment. Using rules for con- 
structing DRSs, the logical forms of the sentences in 
(5) are respectively a and/3. 
el,tl 
pour(j, coffee, el) 
(a) hold(el, tl) 
tl -4 now 
82, t2, 83, t3 
| = cs(e2) 
hold(s2, t2) (#) 
t2 -~ now 
feel-better(j, sa ) 
hold(s3, t3) 
t3 -4 now 
overlap( s2, e 1) 
t2 -4 t3 
The conditions that the event el of pouring coffee 
overlaps with the state s2 of having entered the room 
arises from the discourse use of now in /3. Now 
we must relate /3 to a with a discourse relation. 
The rules that apply are States Overlap and Nar- 
ration. CCT does not apply, because we are not re- 
lating a pluperfect clause to a simple past tensed 
one. By the Cascaded Penguin Principle, we infer 
Background(a,/3). Thus the second sentence in (5) 
describes the background circumstances when Max 
poured himself the coffee. Unlike (4), we do no have 
a situation where we fail to infer which of the per- 
mitted set of discourse relations holds, and so (5) is 
coherent. 
If the comma in (5) is replaced with a full stop, 
then upon failing to attach the second sentence to 
the first (as in (4)), one attempts to attach the third 
sentence to the second to obtain an SDRS which one 
then attempts to attach to the first sentence. At this 
point, CCT won't apply, and so as in (5), we don't 
have a situation where we are unable to infer which of 
the permitted discourse relations holds. So the text 
254 
is predicted to be coherent. The above accounts of 
(3) to (5) show that the Relevance Problem is solved. 
5.3 Parallel and Contrast 
We now give an example of a text in which the rela- 
tion Contrast occurs together with a change in tense 
from the simple past to the pluperfect. 
(14) John was lazy now. But he had worked very 
hard for several years. 
When analysing (14), SDRT will yield two con- 
stituents a and ~ representing the respective sen- 
tences. The presence of the particle but forces a con- 
trast relation between a and fl, but an incoherent 
SDRS may result if the relation is not verified by the 
semantic content and structure of the constituents 
themselves. 
The semantics of Parallel and Contrast are 
explored in depth in Asher (1993). Briefly, 
Paralle~a, ~) or Contrast(a, fl) hold just in case the 
constituents a and /~ have a particular semantic 
structure and content. The semantic structure re- 
quired by Parallel and Contrast is defined in terms 
of embedding trees. Each constituent has an embed- 
ding tree, which depicts the hierarchical structure of 
the constituent SDRSs and the hierarchical structure 
of the DRSs in the SDRSs. The embedding trees for 
the two constituents a and fl of (14) are given below. 
The embedded DRS ff in the embedding tree for fl 
represents the subVRS that characterizes the event of 
working hard introduced by the pluperfect. 
\] 
Briefly, Paralle~a, fl) requires that there is a pair- 
ing of nodes in the embedding trees of a and fl such 
that each pair contains two semantically and struc- 
turally similar objects. Contrast(a,~), on the other 
hand, involves a pairing of nodes from the embed- 
ding tree of a and the embedding tree of fl, such 
that at least some pairs contain structurally similar 
but semantically dissimilar objects. Similarity and 
dissimilarity are exhibited by means of an assignment 
of polarities (+, -) to nodes. Both nodes get + when 
they are similar, one gets + and the other - when 
they are dissimilar. Given a pragmatic constraint of 
novelty or informativeness, no two constituents can 
be perfectly parallel. 
Echoing the distinction between topic and focus 
or given information and new, Asher (1993) isolates 
for each constituent a theme; the constraints on pos- 
sible themes are specified in (Asher 1993). Themes 
may contain arguments and conditions of the SDRSs 
in question; in general, the more of the conditions of 
a constituent that a theme covers the stronger the 
parallel or contrast relation it supports. Parallelism 
between two constituents is maximized when there 
is a common theme and it is as maximal as is com- 
patible with informativeness. Contrast is maximally 
plausible when themes are complementary or even 
contraries. Plausible contrast is defined with respect 
to CE: A plausibly contrasts with B if the KB entails 
A > -,B or B > -,A. 
In our example (14) above, the theme of a that 
is maximal with respect to supporting Contrast 
under the mapping of nodes suggested below is 
lazy(el,j) while the corresponding theme of ff is 
work-hard(e2,j). When paired together the KB im- 
plies that they are plausibly contrastive, assuming 
that world knowledge is stated as intuitions would 
dictate. Thus, contrasting polarities are assigned to 
the paired nodes and Contrast(a, fl) is verified, as 
is required by the presence of but. Thus, the SDgS 
coherently supports Contrast. 
a 
Contrast does not determine any temporal order 
by itself. However, Contrast is compatible with 
Cpp(a, fl), which is inferred in DICE by the Penguin 
Principle. Cpp(a, fl) will force us to conclude that 
the consequent state e# includes ea, which is the 
state of John being lazy. Because of the Consequent 
States axiom, we can infer from this that the event 
of working hard precedes John being lazy. In addi- 
tion, Contrast is compatible with Background, and 
so in this particular case DICE will also force us to 
infer Background(a, fl), since (i) ea is a state, (ii) by 
States Overlap, c~ by default overlaps e~, and (iii) 
by Background, this overlap will by default imply 
Background(a, ~). 
5.4 Perspective Shift 
The analysis of (6) will exploit information flow be- 
tween the lexicon and discourse attachment. 
(6) a. The telephone rang. a 
b. It was Mme Dupont. fl 
c. Her husband had eaten too many oysters 
for lunch. 7 
d. The doctor recommended a change in 
lifestyle. 6 
The analysis of (6) proceeds as follows: let the logical 
forms of the sentences be respectively a to 6. First we 
consider the lexical information in a. Pustejovsky's 
(1991) representation of lexical entries for artifacts 
255 
e, t, z, p, so, tO 
hold(e,t) t -< now 
ring(telephone, e) say(z,p, so) 
hold(so,to) 
~J, Elaboration 
pC_ 
W, S, t t 
husband(w, d) 
":\[='-" I \[ eat-too-many-oysters(w, e) hold(s, t') 
t t ~ now 
t' -4 to 
Figure 1: The SDRS representing Text (6) 
includes a representation of their telic roles, which 
intuitively define the purpose of the artifact. We 
assume that the telic role of a telephone is to have a 
conversation. This telic role invokes three thematic 
roles, identified below by z (the speaker), p (the thing 
that's said), and y (the listener). 
• From the Lexicon: 
telephone > z said that p to y 
This lexical information influences discourse attach- 
ment: upon attempting to attach 8 to a, the reader 
infers that Mme Dupont can fill the role z, and so by 
default, she does. Having identified Mme Dupont as 
filling this role, the rule Elaboration below applies. 
Elaboration captures the intuition that if 8 is to be 
attached to a with a discourse relation, and 8 iden- 
tities a role in a, then normally, Elaboration(a,8) 
holds. 
• Elaboration: 
(% a, 8) A/3 identifies a role in a > 
Elaboration(a, 8) 
By the Penguin Principle on Narration and Elabora- 
tion, Elaboration(a, 8) is inferred. 
Now the task is to update this SDRS with 7: a 
and 8 are both open constituents. Caenepeel (1989) 
argues that if the discourse context induces a psycho- 
logical perspective of a protagonist z, and the clause 
currently being processed is stative, then that cur- 
rent clause is interpreted with respect to z's point 
of view. In this example, the context provided by 
a does induce a psychological perspective because 
the above telic role invokes the propositional atti- 
tude said that. Furthermore, 7 is in the pluperfect, 
and therefore is stative. This motivates Caenepeel's 
Axiom below: it states that a pluperfect sentence 7 
by default identifies the proposition p in the propo- 
sitional attitude ~b invoked by a: 
• Caenepeel's Axiom: 
(r, a, 7) A PP(7) A ~(a, p) > 7 identifies p 
Now consider the reasoning behind attaching 7 
to the preceding open constituent a. The rules 
that apply are Narration, States Overlap, COT and 
Caenepeel's Axiom. Nothing in the reader's KB con- 
flicts with the consequent of Caenepeel's Axiom, and 
so its consequent is inferred; i.e., 7 identifies p. CCT 
conflicts with Narration, and so Upp(a, 7) is inferred 
by the Penguin Principle. Because 7 identifies p, 
Elaboration applies, and whilst conflicting with Nar- 
ration, it's more specific, and so Elaboration(a, 7) is 
inferred. Elaboration(a,8) entails a # 8 by Elabo- 
ration's semantics in SDRT. So in attaching 7 to 8, 
Continuation fires and Continuation(8, 7) is inferred. 
The full representation of (6) is given in figure 1. 
The relic role for telephone has been identified, and 
so say(z,p, so) is added to the DRS representing a. 8 
and 7's DRS conditions then identify the roles: d = z 
256 
in ~ (i.e., Mine Dupont is the speaker on the phone), 
and p C_ 7 in 7 (i.e., what was said over the phone 
is denoted by 7). So, ot contains a propositional atti- 
tude of saying, which given the other DRSS, holds be- 
tween Mme Dupont and the proposition denoted by 
7. 3 Thus the representation of (6) encodes the per- 
spective shift that occurs when interpreting 7, and 
so solves the Perspective Problem. And note that 
elaborations can actually affect the truth conditions 
of DgSS by specifying arguments of event types: in 
this case, recognising the elaboration enabled d - z 
and p _C 7 to be added to the DRS conditions. 
5.5 Attaching Pluperfects Together 
Now consider text (1). 
(1) a. Alexis was a very good girl by the time 
she went to bed yesterday. 
b. She had helped her mum with the house- 
work. 
c. She had practised her piano. 
d. She had done all her homework. 
e. We all felt very good about it. 
One infers Elaboration between (la) and each of the 
pluperfect clauses (lb), (lc) and (ld) using a similar 
strategy to that outlined in the analysis of (13). We 
now examine in detail how the pluperfect clauses are 
related to each Other. (lb) is an open clause to (lc), 
and just as in (8), Background is inferred via the Cas- 
caded Penguin Principle: the pair of conflicting laws 
are States Overlap and Narration and Background 
and Narration. Continuation also applies, given the 
Elaboration relations already inferred, and so Con- 
tinuation is inferred; Continuation conflicting with 
neither Background nor Narration. 4 A similar line 
of reasoning applies when attaching (ld) to the open 
(lc), and so one infers Background and Continuation 
to relate these constituents as well. Finally, further 
pragmatic knowledge that is encoded in race form a 
Nixon Diamond when attempting to attach (le) to 
(ld) thus inducing a discourse pop to (la) (we omit 
the details of this here). Thus the discourse structure 
3 We have used the traditional representation of propo- 
sitional attitudes in DRT, outlined in Asher (1986), 
Kamp (1991b) and Zeevat (1986). 
*Again, the predicates are sufficiently independent 
that we can divide up the nonmonotonic reasoning in 
this way. 
of (1) can be pictorially represented as follows: 
Background 
la 
Elabora~ 
lb ' lc " ld 
Continuation ' Continuation 
Background Background 
' le 
All we have inferred for (1b-d) is that the conse- 
quent States overlap; this doesn't constrain the rel- 
ative starts of the states. So the events described 
in the pluperfect clauses remain unordered, in agree- 
ment with intuitions. 
A more specific rule than States Overlap, if con- 
flicting with it, may induce orderings among the plu- 
perfect clauses. In the analysis of (2), we assume 
there are more specific rules than States Overlap, 
that convey (a) the pragmatic effects of list-type dis- 
course structures; and (b) knowledge concerning the 
normal course of events when climbing a mountain. 
These rules favour Narration being inferred, by de- 
fault. And by the Penguin Principle, these laws deem 
States Overlap irrelevant, and so we will infer Nar- 
ration, rather than Background, between the pluper- 
fect clauses in (2). Narration imposes precedence 
relations between the consequent states, and so the 
textual order of the events matches their temporal 
order. Thus DICE provides the means to solve the 
Interaction Problem. 
6 Conclusion 
We have solved some critical problems about the 
way the pluperfect tense affects the temporal struc- 
ture and rhetorical structure of narrative text. We 
have argued that contrary to the Reichenbachian ap- 
proach, the discourse role of the pluperfect must take 
the reader's background knowledge into account. We 
have provided an anMysis in which the pluperfect is 
viewed as a syntactic discourse marker, which indi- 
cates that only a restricted set of discourse relations 
are permitted in order to attach the current clause to 
the preceding text. We viewed the simple past and 
pluperfect as sententiaily equivalent, although they 
play distinct discourse roles because of the different 
constraints they impose on coherent discourse. 
When attaching a pluperfect sentence to a simple 
past tensed one, the task is to infer which of the 
four discourse relations Ezplanation, Parallel, Con- 
trast or Elaboration hold. Information about causa- 
tion can be used to infer Ezplanation. Information 
about structural and semantic similarities and dis- 
similarities can be used to infer Parallel and Con- 
trast. And information obtained from the lexicon 
can be used to infer Elaboration. For example, the 
257 
lexicon provides potential thematic roles which the 
pluperfect clause can identify: if it does, then this re- 
sults in an Elaboration at the discourse level. In this 
sense, the pluperfect provides a forum in which to 
explore how information at the lexical level interacts 
with information at the discourse level. 
In the light of this, analysing the pluperfect re- 
quires an integrated account of lexical and discourse 
processing. But this is beyond the scope of this pa- 
per. Further research must be pursued in lexical se- 
mantics, that addresses the problem of how rhetori- 
cal information influences lexical processing. Like- 
wise, the theory of discourse attachment must be 
augmented with a detailed account of how informa- 
tion flows from the lexicon to the textual level. Both 
of these issues are explored in (Asher and Lasearides 
1993). 
Acknowledgements 
Thanks to Mario Borillo, Myriam Bras, Mimo 
Caenepeel, Uwe Reyle and two anonymous review- 
ers for their helpful comments on earlier drafts of 
this paper. 
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