Download LING2011 Language and Literacy 2001-2002

Introduction to Cognitive Science:
Linguistics Segment
Lecture 1
September 15, 2005.
(2.00 p.m. – 3.50 p.m.)
Venue: Meng Wah Complex Room 324
Lecturer: Dr. A. B. Bodomo
Department of Linguistics
<[email protected]>
Course Outline and heuristics
Refer to Course Outline:
• course objectives
• format of teaching
• reading materials
• assignments
• study questions
2
Linguistics as Cognitive Science
• Cognitive science is a relatively new discipline that investigates the way the
human mind functions and how computers can simulate these functions. The
human mind is a complex system that receives, stores, processes and sends
out information. All this involves cognition, which refers to perceiving and
knowing.
• Language is an important part of this cognitive process of receiving, storing,
transforming and sending out information. We often hear or read information,
store what we hear or read in order to remember it, and process this
information before telling, or writing to, someone about it.
• Linguistics is the science of language, and is thus the part of cognitive
science that addresses issues of language learning, production, and
understanding. Students of cognitive science need to have a good grasp of
this central aspect of the discipline.
• To this end, in the linguistics component of this introduction to cognitive
science, we will address issues that center on the nature of language, its key
properties and components, and how it is learnt and used in various contexts.
3
Philosophy
Computer
Science
It is
the Scientific Study of the nature
and structure of human language and
A Linguist is not just a
how it is used in various contexts.
polyglot, but a thinker,
COG
specialist in the general
SCI
subject matter
of
Physiology
Linguistics
language(s).
Psychology
4
Many Approaches to Linguistics
• Diachronic/historical approaches: how languages change
over time
• Sociological approaches: how languages vary according to
different classes of speakers
• Mentalistic/cognitive approaches: an investigation of
language as a product of the mind i.e. language as a
cognitive process…
• Descartes…
• Chomsky…
• So how is reality represented through natural language? At
which levels of language can we conceptualise objects and
concepts?
5
Pronunciation:
Level of Phonetics/Phonology
WHITE DOVE /
/
baak6 gaap2
6
Word Form/ Structure:
Level of Morphology
• Two morphemes: {white} and {dove}
• Cantonese (Hong Kong Chinese):
– hoeng1 gong2 dak6 bit6 hang4 zing3 keoi1
'The Hong Kong Special Administrative Region (HKSAR)’
– hoeng1 gong2 wui6 ji5 zin2 laam5 zung1 sam1
‘The Hong Kong Convention and Exhibition Centre’
7
Phrase/ Sentence Structure:
Level of Syntax
WHITE DOVE
• PS rule:
NP  A + N
• Tree diagram:
NP
A
|
white
N
|
(1) Who did you see Chan with?
(2)*Who did you see Chan and?
(3) ngo5 heoi3 zung1 waan4
(4) heoi3 zung1 waan4
(5)*zung1 waan4 heoi3 ngo5
dove
8
Meaning:
Level of Semantics
What does the sign, white dove, mean?
Signifier and signified Reality, Mind, etc.
• English:
a. Chan loves you more than
Yan.
could mean:
b. Chan loves you more than
Yan loves you.
c. Chan loves you more than
Chan loves Yan.
• Cantonese:
a. me1 waa2 ?
could mean:
b. What did you say ?
c. What language ?
9
Meaning:
Level of Pragmatics
• What would white dove mean in some
specialized contexts, cultures, etc.?
• Pragmatics: meaning in context
– It’s hot!!
hou2 jit6 aa3
10
Topics in the linguistics component
•
•
•
•
•
PHONOLOGY
MORPHOLOGY
SYNTAX
SEMANTICS
LANGUAGE and LITERACY ACQUISITION
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Introduction to Cognitive Science
Linguistics Component
Topic 1:
Phonology and Morphology
Keywords
•
•
•
•
•
•
•
•
Phonology
phonetics
phone
phoneme
tone
stress
toneme
tonology
• morphology
• inflectional
morphology
• derivational
morphology
• morph
• morpheme
• morphophonology
• morphophoneme
13
Introduction
• Theme
– A survey of how linguistic knowledge at the level of phonology and
morphology is represented and computed in the minds of
speakers of a language.
• Objective
– an understanding of the basic terms and issues in phonology and
morphology
– an interface approach: rather than rigidly discussing these issues
from phonology, morphology, syntax and semantics, we will look
at how phonology interfaces with morphology and how syntax
interfaces with semantics.
14
Phonology
• A field of cognitive science that investigates how sound
systems of a language are represented in the minds of
speakers
• Stillings et al (1995:220) gives a concise specification of
what phonological knowledge as represented in the minds of
speakers is:
– The phonological component of a grammar consists of a
list of the words of that language, with the pronunciation
of each word given as a faithful acoustic image coupled
with direct instructions to the vocal tract about how to
produce that image, and instructions to the perceptual
system about how to recognize it.
15
Phonetics and Phonology:
A distinction
• Phonology
• Phonetics
– a science that deals
with the articulatory
and acoustic
properties of
sounds produced
by the vocal tract
– how a set of the
sounds produced by
the vocal tract are
organized into
meaningful sound
units in each
language
16
Phonetics and Phonology (cont’d)
• IPA chart (please refer to your own copy)
• For instance, given a list of sounds that can be
produced by the vocal tract, such as in the IPA chart
(Phonetics), only a set of these sounds are meaningful
in each of English, Cantonese and Dagaare
(Phonology).
17
18
Sets of meaningful sounds in
English, Cantonese, and Dagaare
These meaningful sound units are called phonemes.19
Phonemes
• Concrete sounds or phones give us the abstract
concept phoneme – a minimal meaningful sound unit
• basic units in phonology
– phoneme
– allophone
• phonemes in WHITE DOVE as conceptualised/
represented in the minds of speakers:
–/
//
//
/+/
//
//
//
/
20
Allophones
• Variants of a phoneme
• Examples:
– English:
• [p] and [ph] as in /
/ stop and /phit/ pit
– Cantonese:
• [n] and [l] as in /nei5/ and /lei5/ you
– Dagaare:
• [h] and [z] as in /
/ and /
/ yesterday
21
Minimal pairs
• Method for identifying • Examples in English, Cantonese,
and Dagaare:
phonemes - analysing
– English
minimal pairs
• /sip/  /s/, /tip/  /t/
• a minimal pair: a pair of
• /pit/  /p/, /bit/  /b/
words that are identical
except for a contrast in
– Dagaare
ONE sound .
• /
/ to enclose  /l/ ;
/
/ to pull  /t/
22
Suprasegmental phonemes:
Tone and Stress
• Stress
• Tone
– the amount of force
used in pronouncing a
syllable
– meaningful pitch
variations on syllables
Stress and Tone can indicate
differences in meaning among
pairs of words
23
Word stress in English
• Syllables may be stressed or unstressed in
English, and some variations of stress on syllables
of a word may cause differences in meaning.
– Teachers in this course are going to ensure an
'increase of marks for cognitive science
students.
– Teachers in this course are so kind that they will
in'crease your marks.
24
Tone in Cantonese
• Cantonese: TONES
• 6 tonemes:
– high (tone 1), high rising (2), mid level (3), low
falling (4), low rising (5), low level (6)
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Tone in Dagaare
• Two tonemes - high and low
/
/
/ - to smell /
/ - to drink /
/
/
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Phonological rules
• /Underlying phonological representations/
|
• Phonological rules
|
• [Phonetic representation]
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Phonological rules in
English, Cantonese, and Dagaare
English
•/p/  [ph] / # —
•a stop is aspirated in word initial position.
•*pit but phit
Cantonese
•Final stops like /p/, /t/ and /k/ are not pronounced.
•E.g.
Dagaare
•a /d/ becomes [r] in secondary syllable position:
•*dide but [dire] ‘eating’
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Morphology
• the field of cognitive science which studies how
knowledge about the form or internal structure of
words are represented and processed in the
minds of speakers.
• divided into two main parts, inflectional morphology
and derivational morphology
• Basic units of morphology: morpheme, allomorph
29
Morphemes
• A morpheme is a minimal distinctive unit of grammar
(Crystal 1997). A morpheme is an abstract term that must
be captured by a concrete realization, the morph – discrete
speech unit e.g. {white} {dove}
– [In morphology we represent units with braces.]
• {white} {doves}
• Free morpheme: {white} {dove} (these can stand
on their own)
• Bound morpheme: (-those that must be attached to
another morpheme e.g. {–s})
30
Morphology (cont’d.)
• inflectional morphology and derivational morphology.
• Inflectional morphology : knowledge through which
speakers of a language create several paradigms of the same
word to express various grammatical categories like number,
person, tense, aspect, case, and gender:
Number in English:
{paper} – {paper-s}
{dog} – {dog-z}
{prize} – {prize-iz}
But also:
{child} – {child-ren}
{foot} – {feet}
{sheep – sheep} : zero morph
The various plural variations are said to be
allomorphs of the same plural morpheme.
31
Examples of inflectional morphemes
(cont’d.)
• Person and number in
French:
–
–
–
–
–
–
• Aspect in Cantonese:
– {maai5}
Je {mang-e} – I eat
• ‘buy’ – {maai5-zo2}
Tu {mang-es} – You eat
• ‘has bought’
Il {mang-e} – He/she/it eat
– {wan2} ‘play’
Nous {mang-eons} – we eat
• {wan2-gan2}
Vous {mang-ez} – You (pl) eat
• ‘is playing’
Ils {mang-ent} – They eat
32
Derivational morphology
• Derivational morphology or
word formation morphology
on the other hand, is
concerned with the speaker
knowledge that underlies
processes that form new
words out of existing ones
by adding various affixes,
which are pieces of words.
• English: Causative
verbs from nouns and
adjectives
– {energy} – {energ-ize}
– {sterile} – {steril-ize}
– {penal} – {penal-ize }
33
Examples of derivational morphemes
(cont’d)
• Cantonese:
–
–
–
–
• Dagaare: agentive nouns
from verbs
{zai2} (little/small) as in:
– {di} ‘to eat’ - {di-raa} ‘eater’
{dang3 zai2} (small chair),
‘some one who can eat a lot’
{syu1 zai2} (booklet)
– {zo} ‘to run’ – {zo-raa} –
{ toei2 zai2} (small table)
‘runner’, ‘athlete’
– {
{
} ‘roam’ –
}
‘roamer’, ‘tourist’
34
Morphophonology
• While it is possible to talk of phonology and
morphology independently, in reality, knowledge
about these two areas are intertwined, and
speakers process these as such.
• Sometimes, speakers represent knowledge
about phonemes (meaningful sound units) based
on knowledge about some grammatical
environments.
35
Morphophonology
or morphophonemics, as it is known in North America
• the aspect of cognitive science that studies the classification
of phonological aspects of knowledge representation based
on knowledge about the grammatical aspects that affect
these phonological representations and vice versa.
• Morphophoneme:
– in parallel with a phoneme. While phonemes are written surrounded
by slashes / /, morphophonemes are surrounded by braces { }.
They are often written in CAPITALS (Crystal 1997).
36
Morphophonemic examples in English
• phonologically unpredictable singular – plural alternation
of words:
– Knife – knives
– Thief – thieves
– But NOT of
• Chief – *chieves (chiefs)
• The morphophoneme: {F} would then have
morphoallophones like [f] for singular and [v] for plural of
these words.
• Hence the need to emphasize their interrelationship.
37
Other examples of
morphophonological phenomena
• Word or lexical stress is a morphophonemic operation
• Example: in describing the rules of pronunciation we
often appeal to positions of the word in which the
sound is:
– aspiration in English: a voiceless stop in word initial
position is aspirated, elsewhere i.e. in word median and
word final, it is unaspirated. This is not just a phonological
rule but a morphophenemic rule.
38
Conclusion
• Phonology and morphology are two salient aspects of the tacit
knowledge of speakers of a language. It is at these levels of
mental representations that speakers capture the sounds and
structure of words and other minimal meaningful units of speech.
• An interface approach emphasizes that these two must not be
separated into watertight compartments, but must recognize that
there is an intimate interrelationship between them. This
interrelationship is explored in the cognitive area of
morphophonology.
• Morphology can also interface with syntax to give us
morphosyntax. Syntax is going to be one of the topics of
discussion in the next lecture.
39
References
• Crystal, David. 1997. A Dictionary of Linguistics and Phonetics.
Blackwell Publishers.
• Lepore, Ernest and Zenon Pylyshyn (eds). 1999. What Is
Cognitive Science. Blackwell Publishers. (especially chapters 10,
11, 12, and 13).
• Stillings, Neil and others. 1995. Cognitive Science: An Introduction.
MIT Press. (especially chapters 6).
• Trask, R. L. 1993. A Dictionary of Grammatical Terms in
Linguistics. Routledge.
• Wilson, R. and Frank C. Neil (eds) 1999. The MIT Encyclopedia of
the Cognitive Sciences. MIT Press
40
Introduction to Cognitive Science
Linguistics Component
Topic 2:
Syntax and Semantics
Keywords
•
•
•
•
•
•
•
•
Syntax
the mental lexicon
phrase
noun phrase (NP)
verb phrase (VP)
phrase structure
sentence structure
tree diagram
•
•
•
•
•
•
constituent structure
functional structure
semantics
pragmatics
morphosyntax
syntax-semantics
interface
• ambiguity
42
Introduction: theme and objective
• Theme
– A survey of how linguistic knowledge at the level of syntax and
semantics is represented in the minds of speakers of a
language.
• Objective
– an understanding of the basic terms and issues in syntax and
semantics/pragmatics
– an interface approach: rather than rigidly discussing these
issues from phonology, morphology, syntax and semantics, we
will look at how syntax interfaces with semantics.
43
Syntax
• deals with the combination of words to form phrases and
sequences.
• What are the principles that determine ways we can or cannot
combine some words to form sentences?
• For example, why are some of these sentences correct and
others wrong?
– Who did you see Mary with?
– *Who did you see Mary and ?
– Ngo5 heoi3 zung1 waan4 ‘I’m going to Central’
– Heoi3 zung1 waan4
– * Zung1 waan4 heoi3 ngo5
44
• Syntacticians, or cognitive scientists working on syntax,
attempt to capture this knowledge by positing rules.
• Consider the situation whereby a speaker of English,
Cantonese or Dagaare wants to express the conceptual
notion of drinking water in English, Cantonese or Dagaare.
• The first step is presumably to search in a database of words
in their respective languages for the appropriate words to
express the situation.
Let us call this the mental lexicon.
45
The mental lexicon of a language
• a database containing a list of all the words in
the language, along with information about
their grammatical category, how they combine
with other words and ,of course, their meaning.
46
Simplified lexicons of English, Cantonese, and
Dagaare
(each containing words that would express the conceptual notion of a man
having drunk water )
English: ‘The man drank water.’
drank, verb, trans. ‘having ingested water through the mouth’
man, noun, count, ‘an adult male human being’
the, article, DEF.
water, noun, mass ‘a kind of liquid’
Cantonese:
• go3, CL
• naam4 jan2, noun, count ‘man’
• jam2, verb, trans. ‘drank’
• soei2, noun, mass ‘water’
47
Phrase Structure
• From the database of lexical items that would form the building blocks
of linguistic structure expressing the conceptual notion, the next step is
to group the words such that they would express the entities that take
part in the action and the action itself.
• We would refer to this group of words as phrases, a phrase being
defined as a structured group of words.
• Phrases have heads, a head of a phrase is the most important word in
the phrase. Phrases take their names after the name of their heads. So
a noun phrase (NP) is headed by a noun, verb phrase (VP) by a verb,
etc.
– ‘The man’ is an NP, ‘drank water’ is a VP. Indeed, a VP can contain
an NP, water, which just has only one item.
48
Sentence Structure
• words we need to
express a situation are
selected from our
mental lexicon.
• we have successfully
grouped them into
phrases and units to
express entities and
events.
• we are ready to put these
words to form complete
strings expressing the
conceptual situation. This
is the domain of sentence
analysis. We begin by
positing phrase structure
rules.
49
Phrase Structure rules
–
–
–
–
–
–
S
VP
NP
V
N
Art






• With these phrase structure
rules and the lexicon attached
the native speaker can form or
interpret grammatical
sentences and reject
ungrammatical ones.
NP + VP
V + NP
Art + N
drank
man, water
• (In groups of two, spend at most 3
the
minutes and come up with phrase
rules for Cantonese and Dagaare to
express the conceptual situation of a
man having drank water.)
50
A constituent structure diagram in
the form of a tree structure
S
NP
VP
NP
Art
The
N
V
N
man drank water
The first NP functions as the SUBJECT of the sentence, the verb as the
PREDICATE and the second NP as the OBJECT.
This can be represented in a functional structure diagram
51
Functional structure diagram
PRED ‘drink <SUBJECT, OBJECT>’
TENSE PAST
SUBJECT [The man]
OBJECT [water]
• This is how we represent the syntactic knowledge of
speakers of a language for basic sentences. There are
however more complex cases.
An account of the syntax alone is not enough for an adequate
interpretation of sentences that encode concepts, situations
and attitudes. We need a level of meaning to achieve this.
52
Meaning: level of semantics/
pragmatics
• What does the sign, white dove, mean?
Signifier and signified
– Reality, mind, etc
• This will be taken care of by semantics and
pragmatics
53
Semantics
• Trask (1999: 249)
• Crystal (1997: 343)
– ‘the branch of
linguistics dealing
with meanings of
words and sentences’.
– ‘a major branch of
linguistics devoted to
the study of
MEANING in
language’.
54
Meaning:
Level of Semantics
• English:
a. Chan loves you more
than Yan.
could mean:
b. Chan loves you more
than Yan loves you.
c. Chan loves you more
than Chan loves Yan.
• Cantonese:
a. me1 waa2 ?
could mean:
b. What did you say ?
c. What language ?
55
Meaning:
Level of Pragmatics
• Crystal (1997: 301)
– ‘the
study of language from the point of view of the users,
especially of the choices they make, the constraints they
encounter in using language in social interaction, and the
effects their use of language has on the other participants
in an act of communication’.
What would white dove mean in some specialised
contexts, cultures, etc.?
•What about a black tie?
56
Syntax and how it interfaces with
other components
• Morphosyntax
• The syntax-semantics interface
57
Syntax and Its Interfaces (Morphology)
• Interface with morphology
 morphosyntax
– There is a close relationship between the structure
of words and the structure of sentences.
– In some languages it is even difficult to tell whether a
particular word formation is a word or a sentence:
58
Syntax and Its Interfaces (Morphology)
– Swahili (a language of East Africa):
ninakupenda
• Is a word that is made up of:
ni- naku - penda
I Tense you love
(The item –na- in this language marks tense.)
• In this language, this word structure can also stand as a
sentence, thus:
Ninakupenda
'I love you'
59
Morphosyntax (cont’d.)
In the data above, it is better to analyse this linguistic item
both in terms of its morphology and syntax, hence morphosyntax.
• Trask (1999:176)
– ‘the area of interface between morphology and syntax’.
• Crystal (1997:250-251)
– grammatical categories or properties for whose definition criteria
of morphology and syntax both apply, as in describing the
characteristics of words’
– E.g. NUMBER in nouns constitute a morphosyntactic category:
• number contrasts affect syntax (e.g. singular subject
requiring a singular verb)
• they require morphological definition (e.g. add -s for plural)
60
The Syntax-semantics Interface
• Besides studying the formal structure of sentences it is also
important to study how parts of the sentence contribute to an
interpretation of the whole sentence.
• Such is especially the case with syntactically ambiguous
sentences:
– Chan loves you more than Yan .
• Could mean:
i. Chan loves you more than Yan loves you .
ii. Chan loves you more than Chan loves Yan.
• [Class should look for more syntactic ambiguities in English,
Cantonese, and any other language]
– e.g. I hit the man with a book.
61
Conclusion
• We have briefly shown how tacit linguistic knowledge
can be represented at various levels of phonology,
morphology, syntax, semantics, pragmatics, and their
interfaces, including morphophonology,
morphosyntax, and the syntax-semantics
interrelationships.
• In the next lecture/topic, we shall look closely at how
this linguistic knowledge representation can be
formalised into an algorithm, a computational procedure
for processing this linguistic knowledge.
62
References
• Crystal, David. 1997. A Dictionary of Linguistics and Phonetics.
Blackwell Publishers.
• Lepore, Ernest and Zenon Pylyshyn (eds). 1999. What Is
Cognitive Science. Blackwell Publishers. (especially chapters 10,
11, 12, and 13).
• Stillings, Neil and others. 1995. Cognitive Science: An Introduction.
MIT Press. (especially chapters 6).
• Trask, R. L. 1993. A Dictionary of Grammatical Terms in
Linguistics. Routledge.
• Wilson, R. and Frank C. Neil (eds) 1999. The MIT Encyclopedia of
the Cognitive Sciences. MIT Press
63
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