Table Of ContentTense, Aspect Temporal Reference
and
Marc Moens
Ph. D.
University Edinburgh
of
1987
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Declaration
I declare has been by
that this thesis composed myself and that the research reported therein
has been by indicated.
conducted myself unless otherwise
Edinburgh, September 15,1987
Acknowledgements
Before I begin I like have
to tell to
my story, would mention a number of people who played
important it dissertation.
an part over the years took me to complete this
Mark Steedrnan, I forced by
who suggested to me the topic of tense and aspect. see myself
him for There is idea in dissertation
the to thank this. this
rules of etiquette probably no which
I did discuss Mark lunch, dinner, drinks during in his
the
not with over or many sessions
-
And be he fixed
times to
office. when got really rough and nothing seemed going well, my car
itself His friendship
radio and said that everything else would sort out as well. support and
have beyond for.
thank
gone what one can someone
Barry Richards, kept holes in I him
to
who as a supervisor punching whatever presented as
If is in follows, it is due in
argument. there some coherence what certainly no small respect to
his debate issues.
continuing willingness to the
My friends Centre, for
the
and colleagues at remarks and comments at workshops or seminars.
I hope dissertation finally jokes like "Are feeling
that submission of the will put a stop to you
" "Isn't it ".
tense? time talk?
and about you're giving a
Mijn die bleven doorheen de jaren, hebben
ouders, me steunen ook al ze zich waarschijnlijk
het lang duurde.
toch
vaak afgevraagd waarom zo
And Mimo. (words fail)
4
Abstract
English exhibits a rich apparatus of tense, aspect, time adverbials and other expressions that
locate in
can be used to order states of affairs with respect to each other, or to them at a point
Ideally for
these
time with respect to the moment of speech. one would want a semantics
between
demonstrate
expressions to that an orderly relationship exists any one expression and
it Yet linguistic formal leave
the meanings conveys. most existing and semantic accounts
something to be desired in this respect, describing natural language temporal categories as
descrip-
being full indeterminacies,
of ambiguities and apparently escaping a uniform semantic
tion.
from
It will be argued that this anomaly stems the assumption that the semantics of these
is directly linear familiar from logic
expressions related to the conception of time temporal or
be
physics an assumption which can seen to underly most of the current work on tense and
-
involved in
aspect. According to these theories, the cognitive work the processing of temporal
discourse intervals line
consists of the ordering of events as points or on a time or a set of time
lines.
There however, for is
this time the
are, good reasons wondering whether concept really one
linguistic directly it be
that to; that
our categories are most related will argued a semantics of
in defining
temporally referring expressions and a theory of their use the temporal relations of
different
the
events require a and more complex structure underlying meaning representations
is A be developed, based
than the that
commonly assumed. semantics will on assumption
like
tense, to
categories aspect, aspectual adverbials and propositions refer a mental representa-
is
tion of events that structured on other than purely temporal principles, and to which the
notion of a nucleus or consequentially related sequence of preparatory process, goal event and
is
consequent state central.
It be identification is logical
that the the to the
will argued of correct ontology a preliminary
formal being in design
the
choice of any particular representation scheme, as well as essential
language front-ends for databases. It be how
temporal the
of natural will shown ontology
developed here be implemented in database information
that time-related
can a contains about
is be by language
that to
events and queried means of natural utterances.
Contents
Abstract
4
.............................................................................................................................
1. The
temporal 7
procedural study of expressions
.............................................................
2. The tense 14
referential nature of
......................................................................................
2.1 Tense 14
as anaphor
.................................................................................
2.2 Referential 21
temporal
accounts of expressions
.......................................
2.2.1 Reichenbach's 22
times
reference
..................................
2.2.2 Computational 24
approaches
.........................................
2.2.3 Formal 27
approaches
....................................................
2.3 Non-referential 32
approaches
..................................................................
2.4 Problems 34
the
with referential account
.................................................
2.5 Conclusion 36
...........................................................................................
3. Temporal intervals 38
ontologies: points, and events
........................................................
3.1 Introduction 38
.........................................................................................
3.2 Points, intervals, 39
events
.......................................................................
3.3 Conclusion
49
...........................................................................................
4. A typology temporal descriptions 51
of
............................................................................
4.1 Introduction 51
.........................................................................................
4.2 Tense, Aktionsarten 51
aspect and
...........................................................
4.3 The 55
taxonomy
......................................................................................
4.4 Conclusion 66
...........................................................................................
5. An
temporal 67
analysis of expressions
............................................................................
5.1 The 67
aspectual nature of some temporal expressions
............................
5.1.1 For 67
and until
..............................................................
5.1.2 In-adverbials 71
..............................................................
5.1.3 Negation
74
....................................................................
5.2 Progressives Imperfective Paradox 75
the
and
.........................................
5.2.1 Progressive 75
states
......................................................
5.2.2 A functional
79
account
.................................................
5.2.3 The imperfective 86
paradox
..........................................
5.3 Perfects 94
................................................................................................
5.3.1 Some descriptions 94
semantic
......................................
5.3.2 Consequent
96
states
......................................................
5.3.3 McCawley's Comrie's 4
types 101
and of perfect
...........
5.4 The Perfect Progressive
103
.......................................................................
6 Contents
5.5 Conclusion
104
...........................................................................................
6. The discourse
temporal 106
structure of
.............................................................................
6.1 Introduction
106
.........................................................................................
6.2 Temporal Connection
107
..........................................................................
6.2.1 When
107
.........................................................................
6.2.2 Other
temporal 116
connectives
.......................................
6.2.3 Presuppositions descriptions
118
and event
.....................
6.3 The discourse 120
temporal
structure of
....................................................
6.4 Conclusion 129
...........................................................................................
7. The descriptions 130
aspectual classification of event
........................................................
7.1 Introduction 130
.........................................................................................
7.2 Aspectual 130
tenselessness
categories and
...............................................
7.3 Diagnostic tests for the 134
categories
.......................................................
7.3.1 Stative 136
expressions
....................................................
7.3.2 Event 140
expressions
......................................................
7.4 Aspect 145
and compositionality
................................................................
7.4.1 Mass terms, bare 150
plurals and aspectual class
............
7.5 Conclusion
154
...........................................................................................
8. Temporal information for language
156
natural processing
................................................
8.1 Introduction 156
.........................................................................................
8.2 Extracting information from
temporal text 157
..........................................
8.3 Temporal
163
representation models
..........................................................
8.3.1 The 163
situation calculus
................................................
8.3.2 Ontologies
165
temporal
with characteristics
...................
8.3.3 Event-based 171
ontologies
..............................................
8.3.4 Conclusion
175
.................................................................
8.4 An implementation 175
the
of episodic representation scheme
..................
8.4.1 Introduction
175
...............................................................
8.4.2 The database 179
..............................................................
8.4.3 Aspect 184
and aspectual adverbials
................................
8.4.4 Anaphoric 190
tense
and when-clauses
............................
8.4.5 Program 193
and sample session
.....................................
8.5 Conclusion 198
...........................................................................................
References 201
.........................................................................................................................
Chapter 1
The temporal
procedural study of expressions
Our language bias in its Relations date
ordinary shows a tiresome treatment of time. of are ex-
This bias is itself
alted grammatically as relations of position, weight and color are not. of an
inelegance, breach Moreover, form it
or of theoretical simplicity. the that takes that of re-
-
form is
quiring that every verb show a tense peculiarly productive of needless complications,
-
it demands lip is farthest from (Quine
since service to time even when time our thoughts.
1960: 170)
It has been degree
though the
often remarked, not always with same of exaggeration or
is in Quine's
that the temporal
exasperation as exhibited words, expression of relations plays
important in language,
an role and that as an obvious correlate the processing of temporal
- -
information important language
constitutes an part of natural understanding.
It is have been develop logical
therefore that to
not surprising many attempts made systems
function in language. Ideally,
that try to the temporal
give an account of of expressions sys-
like be in
tems these the they
should abstractions of processes people engage as produce and
English is, logic
process sentences; that a of temporal expressions should explain what takes
in information in language
the temporal
place process of relaying and extracting natural
discourse, from
then this that the
and abstract account simple, general rules govern usage of
temporal
expressions.
In information be described
terms, the temporal
very general processing of could as consisting
(for
the the
of construction of a serial representation of events, processes and situations all of
I "states in discourse. Constructing
the term talked the
which will use general of affairs") about
involves
the to the
such a serial representation anchoring states of affairs our conception of
dimension, i. line, lines in
time e. ordering them along the real time or along expected time the
future, imaginary lines These be
or along alternative time now. states of affairs can ordered
instance
with respect to each other, or with respect to some pre-established on the temporal
dimension The
usually, though not necessarily, the moment of speech. cognitive work
-
involved in language
temporal
understanding natural expressions consists of creating and
(cf. Miller & Johnson-Laird
the these
updating particular contents of serial representations
1976: 413).
It important be
seems, then, that an task to carried out when constructing a temporal semantics
Chapter 18 Temporal
expressions
for a natural language is to determine the nature of the underlying time concept that is involved
in
this.
all
As by Bach (1981), try to this kind by
was pointed out one should not answer of question ask-
ing looks like. The
they think the time
native speakers what underlying concept correct
be, from language
approach seems to rather, to work a grammatical analysis of temporal
its basis.
towards an account of conceptual
Yet, for has be formidable To begin
this turned to task.
various reasons, always out a with, as
Miller & Johnson-Laird (1976: 411) information be by
temporal
point out, can conveyed words
in (begin, (year,
all the major syntactic categories, such as verbs end, precipitate, recur), nouns
(recurrent, later), (eventu-
season, precedent, minute), adjectives successive, present, adverbs
(at, during, in) (before,
ally, often, shortly, subsequently), prepositions on, and conjunctions
just An language involve
temporal
as, until, as soon as). analysis of would a study of virtu-
language, be
ally all categories of the and only then would one able to say something about the
language
the natural temporal
conceptual apparatus underlying system.
Moreover, information
that temporal
merely collecting all expressions convey and studying
import interact in
their these
semantic will not suffice, since many of expressions complicated
inexplicable in Thus, it
patterns, revealing unexpected and often seemingly changes meaning.
like describe
to the
would seem a straightforward and attainable goal semantics of a simple
for describe
present tense; such an account could, example, the present tensed state of affairs
holding, in (la):
as true at the moment of speech or as currently as
(1) (a) John loves Mary
Yet, drastically in
the this tense to
meaning of simple morpheme seems change rather combina-
different (as in lb), in
tion with a verb of a type and yet again combination with an adverbial
in (c) (cf. Miller & Johnson-Laird 1976: 412):
as
(1) (b) John kisses Mary
(c) John kisses Mary
today
The in (b) describes habitual
expression an state of affairs, or a running commentary on a
it be
As
specific state of affairs. a commentary, may reporting a past state of affairs using the
is happen. The in (c)
historic present, a currently ongoing one, or one that yet to expression
has happen.
describes
that to
a state of affairs yet
unambiguously
Since in (1) be
the ambiguity exhibited example seems to related to the type of the main verb,
Chapter 19
Temporal
expressions
in be define
the next step the research could to the temporal nature of verbs and classify them
to their temporal A like love, for be
according profile. verb example, could classified as stative,
different interpretation in
giving rise to a semantic when used the simple present than
an event
like kiss. And kiss describes
verb whereas an event that can take some time, an event verb
like discover be described being illustrated in (2a). But
could as punctual or non-extended, as
influence is illustrated in
these temporal profiles can change under the of other expressions, as
(2b) (c) discover has iterative (cf. L. Carlson 1981):
and where an meaning
(2) (a) I discovered hidden in
an old staircase my cellar.
(b) I discovered beach in Corfu last
many a nice summer.
(c) Many discovered beach
the
people white sandy near
the this
olive yard year.
Hurtig (1974) intractable
notes an even stranger and apparently more related phenomenon,
illustrated in (3):
(3) (a) For 12 Mary her
than
more years, shared all worries and
joys dead
with the man.
(b) For 12 Mary her
than
more years, shared all worries and
joys dead
with a man.
The information be
temporal
wide range of grammatical categories with which can expressed,
interaction between fact
the complicated patterns of them, and the that one and the same
diverse has it
temporal
expression can convey a set of seemingly unrelated meanings made
difficult discern language. The
to the temporal
any systematic principles underlying grammar of
language discover basis
to the then these
strategy of analyzing underlying conceptual and use
build logic for language doomed failure.
concepts to a temporal natural expressions seems to
Because insurmountable began building formal
of these apparently problems, researchers their
from direction, frameworks bor-
accounts the opposite taking as their starting point conceptual
from logical language.
the time, these to the
rowed study of and applying study of
At first blush, have lot it. After logi-
this strategy also seems to a to commend all, temporal
have
cians studied extensively the nature of time and can provide us with a conceptual
All is it is
apparatus the properties of which are well understood. that needed, so seems, an
how language
account of natural expressions map states of affairs onto this conceptual struc-
ture.
And is in One its
this
yet, strategy very misleading a number of ways. of misconceptions, the
deep-rooted one, has to do with the very structure of time. Most temporal logicians
most will
Chapter 1
10 Temporal
expressions
agree that time consists of past, present and future, and that the future is just like the
past
-
from fact it follows
apart the that the present rather than preceding it. However, linguists
and
descriptive language data
semanticists concerned with a proper account of natural noted early
basic distinction in language like English is
on that the temporal a twofold, not threefold:
English has device for future from
grammar no whatever cutting time away the time of speak-
ing. (Joos 1964: 135)
On the basis of the tenses, it is possible only to distinguish the past from the non-past. Thus,
(4a) is like (4b) is
clearly past, combining most naturally with an adverbial yesterday; clearly
non-past, not allowing combination with an adverbial referring to a past time:
(4) (a) John
played squash
(b) John
plays squash
As discussed before, tense in (4b) describes habitual
was a present as used probably an or
future like In
state of affairs, combining most naturally with an adverb often or tomorrow.
indicates does its
the tense
other words, present only non-pastness and not on own allow a
further disambiguation between future To in English
time. that
present or communicate some-
is "at be
thing the time", the
really present or going on present progressive can used:
(4) (c) John is
playing squash
But in (c) denotes logicians' is
to say that the expression the present time complicating matters
in (c), describes
rather than resolving them: the present progressive again, only a non-past state
location described in (4c) be both in
the the the
of affairs; actual of state of affairs could
be for future.
the
present, or planned
The found in logics, future is logically
temporal that the
other conceptual notion often viz.
image is in language. As Lyons
speaking the exact mirror of the past, also not reflected
(1977: 677), futurity in language is it
temporal
remarks never a purely concept; necessarily
includes There is
an element of prediction or some related modal notion. no a priori reason
languages future
why could not treat time predictions as grammatically parallel with statements
but in don't.
the they
about past, general
framework
It be from this brief discussion that taking a pre-established conceptual
should clear
lead
to
to study the grammar of temporal relations can very easily unnecessary complications
in the leave things that need explaining.
grammar, or will unexplained
Linguists formal line be
to this of research will then
and semanticists who still want pursue
forced logical framework from. This, in defeats
to adapt the they started off a sense, the pur-
for from
pose of their enterprise: one of the reasons starting off the theories and concepts
