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 <abbodomo@hku.hk> 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 11 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) 25 Tone in Dagaare • Two tonemes - high and low / / / - to smell / / - to drink / / / 26 Phonological rules • /Underlying phonological representations/ | • Phonological rules | • [Phonetic representation] 27 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’ 28 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 - END - 64