MODALITY IN ENGLISH AND VIETNAMESE A COGNITIVE PERSPECTIVE

VIETNAM NATIONAL UNIVERSITY – HANOI
UNIVERSITY OF LANGUAGES AND INTERNATIONAL STUDIES
NGUYỄN THỊ THU THỦY
MODALITY IN ENGLISH AND VIETNAMESE A
COGNITIVE PERSPECTIVE
A Thesis Submitted in Full Fulfillment of the Requirements
for the Degree of Doctor of Philosophy
Major: English Linguistics
Code: 62 22 15 01
Supervisors: Assoc. Prof. Dr. Vo Dai Quang
Prof. Dr. Hoang Van Van
Hanoi, 2015
CERTIFICATE OF ORIGINALITY
I, the undersigned, certify my authority of the dissertation report submitted entitled
“Modality in English and Vietnamese: A Cognitive Perspective” in full fulfillment of the
requirements for the Doctor of Philosophy.
Except where the reference is indicated, no other person’s work has been used without due
acknowledgements in the text of the dissertation.
Hanoi, 2015
Nguyen Thi Thu Thuy
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ACKNOWLEDGEMENTS
Upon reaching this time, I have been fortunate to have benefited from encouragements
and financial supports by my colleagues and Bacninh Teacher Training College where I have
been working for nearly 20 years.
I would like to express my utmost gratitude to my research supervisors: Assoc. Prof. Dr.
Vo Dai Quang and Prof. Dr. Hoang Van Van, for their long lasting supervision, great
encouragements, invaluable guidance and endless support during my research. They give me a
lifetime unforgettable memory of their benevolence, patience, intelligence, diligence and
erudition.
My special thanks are expressed to professors and doctors at the University of Languages

and International Studies, Vietnam National University (VNU): Prof. Dr. Nguyen Hoa; Assoc.
Prof. Dr. Le Hung Tien; Prof. Dr. Nguyen Quang; Prof. Dr. Tran Huu Manh; Dr. Ha Cam
Tam; Dr. Nguyen Huy Ky; Assoc.Prof. Dr. Le Van Canh, Assoc. Prof. Dr. Tran Van Phuoc,
Assoc. Prof. Dr. Phan Van Que, Assoc. Prof. Dr. To Nu My Nhat, Assoc. Prof. Dr. Nguyen
Van Trao, Assoc. Prof. Dr. Pham Thi Hong Nhung, Assoc.Prof. Dr. Hoang Tuyet Minh,
Assoc.Prof. Dr. Ngo Huu Hoang, Dr. Pham Thi Thanh Thuy, Dr. Huynh Anh Tuan, Dr. Do
Thi Thanh Ha, Dr. Nguyen Duc Hoat, Dr. Hoang Thi Xuan Hoa; Prof. Dr. Nguyen Duc Ton;
Dr. Sao Chi, etc. for their long lasting support, great encouragements and useful advice during
the time the study was carried out. I have also benefited from the assistance of other scholars. I
would particularly like to acknowledge the efficiency and expertise of Prof. Dr. Jack C
Richards, Prof. Dr. Alexander Arguelles, Dr. Melchor Tatlonghari during the time I started to
conduct my thesis at SEAMEO Regional Language Center, Singapore.
I also owe many thanks to my students, colleagues and friends who patiently listened to
my frustrations, and provided me with a lot of encouragements, understanding and collegiality.
Their valuable backing indicates the significance of my study. Finally, my wholehearted
appreciation goes to my husband, Mr Nguyen Van Ban, and my two children: Nguyen Xuan
Thang and Nguyen Bich Thuy, my parents, my brothers and sisters; for their emotional and
material sacrifices as well as their understanding and unconditional supports. Their
encouragements and financial aids make all my endeavours worth doing.
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ABSTRACT
This study is an attempt to describe, analyse, compare/ contrast English and Vietnamese root
and epistemic modality as realized by modal verbs from Cognitive perspective, more
specifically in terms of force dynamic framework. The study is both descriptive and
contrastive in nature. The main aim of the research is to find similarities and differences
between English and Vietnamese root senses (including obligation, permission, ability and
volition) and epistemic senses (including necessity, probability and possibility) of modal verbs
from force dynamics.
The main data used in this study are taken from the two corpora: one in English with a total of
500,000 words in 91 social science texts and the other in Vietnamese with 500,000 words in

119 social science texts on the ground that (1) it is a rich resource for the researcher to find
examples of root and epistemic meanings of modal verbs in English and Vietnamese to serve
the purposes of the study and (2) it is the social science field that the researcher often deals
with. The texts are research articles published in English and Vietnamese journals respectively
in 7 disciplines: education, psychology, social science, economy, linguistics, culture and law,
from 2000 upwards. The data collected are then quantitatively and qualitatively analyzed in
order to find similarities and differences between English and Vietnamese root and epistemic
senses of modal verbs in terms of force dynamics in case that English is considered as a source
language and Vietnamese as a comparative one. With the help of the corpus-based analysis -
the TexSTAT-2 programme, frequency occurrences and KWIC (Key Word In Context)
concordance of various modals are discussed in order to show their relative importance in
expressing root and epistemic senses in the two languages in question. The findings of the
study show that both English and Vietnamese writers/ conceptualizers use the modality of
obligation, permission, ability, volition, necessity, probability, and possibility with different
force structures and barriers to express their different opinions or attitudes towards the
propositions/ state of affairs or events. It can be inferred from the results of the study that there
exists one common core across English and Vietnamese modal verbs, i.e., the force opposition
between the Agonist and the Antagonist. The force can be the one which impinges upon the
participant or the state of affair or the event, making the situation necessary (e.g. must in
English and phải in Vietnamese). The force may be the one that prevents the participant or the
situation from taking place (e.g. can’t in English and không thể in Vietnamese). There may be
absence of force, or removal of restraint or no barrier so something is possible (though not
necessary) (e.g. can in English and có thể in Vietnamese). However, there are a number of
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differences between the two languages under study when the conceptualizers/ writers express
their own embodied scientific experiences in communication by using various modals with
different levels of strength of cognitive, sociophysical and rational forces. One of the typical
differences is that in English, low strength forces of modals such as can, could, may, might,
predominate over median (will/ would/ should/ ought) and high strength (must/ have to/ need/
cannot), which indicates a tendency for modality to be used to mitigate than to strengthen

assertations in academic writing. In contrast, in Vietnamese, high strength modals (phải, cần,
không thể) predominate over median (nên, sẽ, muốn, định, toan) and low (có thể), which can
be inferred that the Vietnamese writers/ conceptualizers when writing their papers in social
science journals have a tendency of expressing strong obligation and necessity. The
overweight of high dynamic value in Vietnamese may be due to the fact that the three major
philosophical traditions: Confucianism, Buddhism and Taoism have exerted their influence on
the “subjective culture” of the Vietnamese. (cf. Bochner 1986 & Marr 1981, cited in Ellis 1994
& T.N.Thêm 1998: 25).
It is hoped that the findings from this study will make a contribution to further understanding
of root and epistemic modality in English compared to Vietnamese in terms of force dynamics
and their equivalence and non-equivalence in the expressions of obligation, permission, ability,
volition (in sociophysical interactions and relations), and the modality of necessity, probability
and possibility (in reasoning domain). Moreover, the findings of similarities and differences
between the two languages will be useful in language teaching and learning and translation
from English into Vietnamese and/or vice versa.
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TABLE OF CONTENT
Pages
CERTIFICATE OF ORIGINALITY……………………………………… i
ACKNOWLEDGEMENTS ……………………………………………… ii
ABSTRACT ……………………………………………………………… iii
TABLE OF CONTENT …………………………………………………… v
LIST OF TABLES ……………………………………………………… ix
LIST OF FIGURES………………………………………………………… x
ABBREVIATIONS ………………………………………………………… xi
PART ONE: INTRODUCTION ………………………………………… 1
1.1. Rationale ………………………………………………………………. 1
1.2. Scopes of the Study ……………………………………………………. 2
1.3. Aim and Objectives of the Study ………………………………… 5
1.4. Research Questions …………………………………………………… 5

1.5. Methods of the Study ………………………………………………… 6
1.6. Contribution of the Study …………………………………………… 7
1.6.1. Theoretical Significance of the Study ………………………………. 7
1.6.2. Practical Significance of the Study …………………………………. 8
1.7. Structure of the Dissertation …………………………………………. 8
PART TWO: DEVELOPMENT …………………………………………. 9
Chapter I: Literature Review …………………………………………… 9
1.1. Introduction ……………………………………………………………. 9
1.2. Modality from the Traditional Point of View ……………………… 9
1.2.1. The Concept of Modality ………………………………………… 9
1.2.2. Types of Modality ……………………………………………………. 12
1.2.2.1. Agent-oriented Modality vs. Speaker-oriented Modality ………… 13
1.2.2.2. Extrinsic Modality vs. Intrinsic Modality ………………………… 13
1.2.2.3. Deontic Modality, Dynamic Modality and Epistemic Modality …… 14
1.2.2.4. Root Modality vs. Epistemic Modality …………………………… 16
1.3. Modality in Scientific Writing ………………………………………… 19
1.4. Modality Viewed from Force Dynamics in Cognitive Perspective …. 21
1.4.1. Definitions of Terms ………………………………………………… 21
1.4.1.1. Linguistic Universals ………………………………………………. 21
1.4.1.2. Cognitive Linguistics ………………………………………………. 22
1.4.1.3. Cognitive Semantics ……………………………………………… 22
1.4.1.4. Cognitive Grammar ………………………………………………… 23
1.4.2. Major Principles of Cognitive Linguistics …………………………. 23
1.4.2.1. Language is all about meaning …………………………………… 23
1.4.2.2. Grammar and Meaning are indissociable ………………………… 24
1.4.2.3. Language, Cognition and Culture ………………………………… 24
1.4.3. Force Dynamics and Modality ……………………………………… 25
1.4.3.1. The Notion of Force Dynamics …………………………………… 25
1.4.3.2. Force-dynamic Parameters …………………………………………. 26
1.4.3.3. Features of Force …………………………………………………… 28

1.5. Root and Epistemic Modality in English …………………………… 33
1.5.1. Modality and Modal Verbs …………………………………………. 33
1.5.2. Root Modality ……………………………………………………… 36
1.5.2.1. Obligation …………………………………………………………… 37
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1.5.2.2. Permission ………………………………………………………… 38
1.5.2.3. Ability ……………………………………………………………… 40
1.5.2.4. Volition …………………………………………………………… 40
1.5.3. Epistemic Modality …………………………………………………. 41
1.5.3.1. Necessity ……………………………………………………………. 42
1.5.3.2. Probability ………………………………………………………… 42
1.5.3.3. Possibility …………………………………………………………… 44
1.6. Root and Epistemic Modality in Vietnamese ………………………… 45
1.6.1. Modality and Modal Verbs …………………………………………. 45
1.6.2. Root Modality ……………………………………………………… 49
1.6.2.1. Obligation …………………………………………………………… 49
1.6.2.2. Permission ………………………………………………………… 51
1.6.2.3. Ability ………………………………………………………………. 52
1.6.2.4. Volition …………………………………………………………… 52
1.6.3. Epistemic Modality …………………………………………………. 53
1.6.3.1. Necessity …………………………………………………………… 53
1.6.3.2. Probability ………………………………………………………… 54
1.6.3.3. Possibility …………………………………………………………… 55
1.7. Concluding Remarks ………………………………………………… 55
Chapter II: Research Methodology ……………………………………… 56
2.1. Introduction …………………………………………………………… 56
2.2. Research Questions ……………………………………………………. 56
2.3. Methods of the study ………………………………………………… 56
2.4. Data collection ………………………………………………………… 58
2.5. Corpus - aided analysis ……………………………………………… 64

2.6. Cognitive Framework ………………………………………………… 67
2.7. Concluding Remarks ………………………………………………… 72
Chapter III: Root Modality in English and Vietnamese ………………… 73
3.1. Introduction ……………………………………………………………. 73
3.2. General Findings ……………………………………………………… 74
3.3. Obligation in English and Vietnamese ………………………………. 77
3.3.1. Form ………………………………………………………………… 77
3.3.2. Meaning ………………………………………………………………. 78
3.4. Permission in English and Vietnamese ………………………………. 93
3.4.1. Form …………………………………………………………………. 93
3.4.2. Meaning ………………………………………………………………. 93
3.5. Ability in English and Vietnamese …………………………………… 100
3.5.1. Form ………………………………………………………………… 100
3.5.2. Meaning ………………………………………………………………. 100
3.6. Volition in English and Vietnamese …………………………………. 105
3.6.1. Form ………………………………………………………………… 105
3.6.2. Meaning ……………………………………………………………… 105
3.7. Concluding Remarks …………………………………………………. 110
Chapter IV: Epistemic Modality in English and Vietnamese …………… 113
4.1. Introduction …………………………………………………………… 113
4.2. General Findings ………………………………………………………. 113
4.3. Necessity in English and Vietnamese ………………………………… 115
4.3.1. Form …………………………………………………………………. 115
4.3.2. Meaning ……………………………………………………………… 115
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4.4. Probability in English and Vietnamese ……………………………… 122
4.4.1. Form ………………………………………………………………… 122
4.4.2. Meaning ………………………………………………………………. 122
4.5. Possibility in English and Vietnamese ……………………………… 131
4.5.1. Form ………………………………………………………………… 131

4.5.2. Meaning ………………………………………………………………. 131
4.6. English and Vietnamese Modal Verbs in Different Disciplines …… 138
4.7. Concluding Remarks ……………………………………………… 139
PART THREE: CONCLUSION …………………………………………. 143
1. Recapitulation …………………………………………………………… 143
2. Implication ……………………………………………………………… 148
2.1. For English Language Learning and Teaching …………………………. 148
2.2. For Language Research …………………………………………………. 149
3. Limitations of the Study ……………………………………………… 150
4. Suggestions for Further Study …………………………………………. 150
Articles related to the study ……………………………………………… I
References ………………………………………………………………… II
Appendix A: Titles of English Texts in the English Corpus …………… XVII
Appendix B: Titles of Vietnamese Texts in the Vietnamese Corpus …… XXV
Appendix C: String Matching of Modal Verbs in E and VNese Corpora XXXIII
Appendix D: Tables ………………………………………………………. LXV
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LIST OF TABLES
Table 2.1 Data in English and Vietnamese Corpora 60
Table 2.2 Distribution of Root and Epistemic Modality in the two Corpora 67
Table 2.3 Categories of Low-Median-High FD in English and Vietnamese 68
Table 2.4 Categories of Root Senses in English and Vietnamese 70
Table 2.5 Categories of Epistemic Senses in English and Vietnamese 72
Table 3.1 Distribution of 4 Root Senses in the E and Vietnamese Corpora 75
Table 3.2 Distribution of Low-Median-High FD in the E & VN Corpora 76
Table 3.3 Distribution of E and VNese Modals in Root & Epistemic Senses LXV
Table 3.4 Distribution of E & VNese Modal Verbs in the Two Corpora LXV
Table 3.5. Distribution of Co-occurrence of Modal Verbs in the Vietnamese Corpus LXV
Table 3.6. Distribution of Obligation Realized by Modal Verbs in the E & VNese Corpora 92
Table 3.7 Distribution of Permission realized by Modal verbs in E&VNese Corpora 99

Table 3.8 Distribution of Ability realized by Modal verbs in E & VNese Corpora 104
Table 3.9 Distribution of Volition realized by Modal verbs in E & VNese Corpora 110
Table 4.1 Distribution of 3 Epistemic Senses in the E & VNese Corpora 114
Table 4.2 Distribution of Necessity realized by E &VNese Modal verbs 121
Table 4.3 Distribution of Probability Realized by E & VNese Modal verbs 130
Table 4.4 Distribution of Possibility Realized by E & VNese Modal verbs 137
Table 4.5 Distribution of English Modal Verbs in 7 Disciplines LXVI
Table 4.6 Distribution of Vietnamese Modal Verbs in 7 different disciplines LXVII


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LIST OF FIGURES
Figure 1.1. Cultural thought patterns (Kaplan, 1966: 15) 20
Figure 1.2. Force Dynamic Entities (Talmy, 2000a: 414) 27
Figure 1.3. The basic steady-state force-dynamic patterns (Talmy 2000a: 415) 28
Figure 1.4. Compulsion (Johnson, 1987: 45) 29
Figure 1.5. Blockage (Johnson, 1987: 46) 29
Figure 1.6. Counterforce (Johnson, 1987: 46) 30
Figure 1.7. Removal of Restraint (Johnson, 1987: 47) 30
Figure 1.8. Enablement (Johnson, 1987: 47) 30
Figure 1.9. Langacker’s basic epistemic model (1991a: 242) 31
Figure 1.10. Langacker’s (1991a: 277) Dynamic Evolutionary Model 32
Figure 2.1. String Matching of Must in the English corpus 65
Figure 2.1. String Matching of Phải in the English corpus 66
Figure 3.1. “Narrow scope” deontic should/ ought (Pelyvás 2006: 144) 79
Figure 3.2. (Agonist) need not VP (Talmy 2000a: 454) 82
Figure 3.3. Deontic must (Pelevás 2008) 83
Figure 3.4. 1 (Agonist) must not VP (Talmy 2000a: 454) 85
Figure 3.5. 1 (Ago) has to VP (Talmy 2000a: 447) 85
Figure 3.6. Nên for obligation 87

Figure 3.7. CN + không cần + V 89
Figure 3.8. Deontic phải for strong obligation 91
Figure 3.9. 1 (Ago) can’t VP (Talmy 2000a: 456) 94
Figure 3.10. Deontic may (Pelyvás 2006: 140) 95
Figure 3.11. 1 (Ago) may not VP (Talmy 2000a: 447) 96
Figure 3.12. Có thể for permission 97
Figure 3.13. Blockage không thể 98
Figure 3.14. 1 (Agonist) can VP (Talmy 2000a: 445) 101
Figure 3.15. May- ability (Pelyvás 2006: 140) 102
Figure 3.16. Có thể for ability 103
Figure 3.17. WILL – ‘Wish’, ‘CHOOSE’ (‘Narrow scope’) (Pelyvás 2008) 106
Figure 4.1. Epistemic must (Pelyvás 2008) 117
Figure 4.2. Epistemic phải 120
Figure 4.3. ‘Wide scope’ deontic should/ought (Pelyvás 2006: 145) 123
Figure 4.4. Epistemic will (Pelyvás 2008) 126
Figure 4.5 Epistemic nên 127
Figure 4.6. Epistemic sẽ 129
Figure 4.7. Epistemic may (Pelyvás, 2006: 147) 132
Figure 4.8. Có thể for possibility 135
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ABBREVIATIONS
The following abbreviations are used chiefly in glossed language data examples:
Adv: Adverb Adj: Adjective
CA: Contrastive analysis CG: Cognitive grammar
CL: Cognitive linguistics CN: Chủ ngữ
CS: Cognitive Semantics Eng: English
FD: Force Dynamics Fig: Figure
Mil: million Lm: landmark
L1: First language L2: Second language
No: Number Occ: occurrences

OS: Objective Scene KWIC: Key Word In Context
S: Subject SoA: State of Affair
Txt: Text Tr: trajector
VP: Verb Phrase VNese: Vietnamese
Abbreviations in the two corpora
EEco: English economics VEco: Vietnamese economics
ECult: English culture VCult: Vietnamese culture
EEdu: English education VEdu: Vietnamese education
ELaw: English law VLaw: Vietnamese law
ELing: English linguistics VLing: Vietnamese linguistics
EPsyc: English psychology VPsyc: Vietnamese psychology
ESoci: English social science VSci: Vietnamese social science
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PART ONE: INTRODUCTION
1.1. Rationale
Modality as expressed by modal verbs is an interesting, but complicated linguistic
phenomenon in both English and Vietnamese. Up to now, modality in the English language
has been studied by a number of researchers such as Langacker (1987, 1991ab, 2003, 2008,
2013),Talmy (1985, 1988, 2000a), Taylor (2002), Sweetser (1987, 1990), Johnson (1987),
Coates (1983, 1995), Mulder (2007), Pelyvás (1996, 2000, 2006, 2008), Mortelmans (2006,
2007), Halliday (1994), Declerck (2011), Linden (2012) and some others. Modality in the
Vietnamese language has been investigated by a number of Vietnamese researchers such as
C.X. Hạo (2004), N.T. Hùng (1994), Đ.H. Châu (1996), V.Đ. Quang (2008), N.T. Thìn (2003),
N.M. Thuyết & N.V. Hiệp (2004), D.Q. Ban & H. Dân (2000), N.T. Thuận (2003), P.T.T.
Thùy (2008), N.T. Hùng (2002, 2003), N.V. Hiệp (2007, 2009), B.M. Tóan & N.T. Lương
(2010), D.Q. Ban & H.V. Thung (2012), B.T. Ngoãn (2004), B.T. Đào (2014), etc. However,
there has been almost no research on discussing and analyzing root and epistemic senses of
modal verbs in English and Vietnamese from Cognitive perspective, more specifically in terms
of force dynamics. Therefore, this study is an attempt to describe, analyze, compare/ contrast
English and Vietnamese root modality (including obligation, permission, ability and volition)

and epistemic modality (including necessity, probability and possibility) as realised by modal
verbs from force dynamics (i.e., with regard to linguistic treatment of forces and barriers). The
study mainly follows the narrow definition of modality defined by Lock (1996: 193), i.e. “A
narrow definition of modality encompasses only modal auxiliaries and their uses …”. Modals
in this study mainly refer to Langacker’s study (2003: 3), i.e., modals “are grammaticalized
grounding elements, in which the ground - the speech event and its participants - are ‘offstage’
and subjectively construed’ and have ‘two crucial properties: (1) they are force- dynamic and
(2) the event marked by the complement remains potential rather than actual.’ (Langacker
1999: 308).
The study is primarily an empirical investigation of modality phenomenon (modal verbs)
based on two corpora: one in English with a total of 500,000 words in 91 social science texts
and the other in Vietnamese with 500,000 words in 119 social science texts on the ground that
(1) it is a rich resource for the researcher to find examples of root and epistemic senses of
modal verbs in English and Vietnamese to serve the purposes of the study and (2) it is the
social science field that the researcher often interacts with. The data collected are then
1
quantitatively and qualitatively analyzed so as to find similarities and differences between
English and Vietnamese root and epistemic senses of modal verbs in terms of force dynamics
in case that English is considered as a source language and Vietnamese as a comparative one.
The findings of the study are mainly discussed in terms of force dynamics proposed by some
reputed researchers such as Talmy (1988, 2000ab, 2003); Langacker (1991ab); Johnson
(1987); Sweetzer (1990); Taylor (2002) and Pelyvás (2006).
In fact, the study intends to find the equivalence and non-equivalence between English and
Vietnamese root and epistemic senses of modal verbs from the two main dimensions of
experience: (1) sociophysical area which consists of physical interactions as well as social
relations, practices, and institutions and (2) the epistemic senses of argument, theorizing, and
other activities of reasoning (cf. Johnson 1987 & Sweetser 1990) so that it will help improve
the teaching and learning English in the Vietnamese context.
1.2. Scopes of the Study
This study is to compare/ contrast English and Vietnamese root and epistemic senses as

realized by modal verbs from cognitive analysis frameworks with a view to helping
Vietnamese learners of English to overcome the difficulties if any, related to this language
phenomenon, in their process of language learning and acquisition.
In order to make the task manageable in keeping up with the aim of the study, delimitation is
necessary. The study focuses mostly on a representative sample of modal verbs in English and
Vietnamese. The basic claim here is that these verbs can express both root modality and
epistemic modality which are considered as two main types of modality. The study mainly
follows Lock’s (1996) definition of modality, which is claimed that modality is mainly realised
by modal verbs and their uses. Some researchers such as Hermeren (1978) points out that only
articles, certain prepositions, conjunctions and pronouns rank higher than the modals in the
frequency table compiled from the million-word Brown University corpus. Moreover, works
done by Leech, Rayson & Wilson (2001), P.T.T.Thùy (2008), and N.T.T. Thủy (2012) show
that the main means of expressing modality in English is the set of modal auxiliary verbs.
Recently, much of the research on modality within a cognitive perspective has indeed focused
on modals, more specifically, on the English modals, for instance: Langacker (1991a), Talmy
(1988, 2000a, 2003); Johnson (1987); Sweetzer (1990); Taylor (2002); Pelyvás (2003, 2006),
Mortelmans (2007), Tyler (2008) and Mulder (2007); and this language bias has undoubtedly
shaped the typical intepretation of modality. Therefore, the main focus in this study lies on
2
describing and analysing root and epistemic modality as realized by the core English modal
verbs such as can, could, may, might, must, will, would, shall, should; and semi-modals such as
ought to, have to and need with examples mainly taken from the 500 000-word corpus
including 91 English social science texts. Have to is included in this set on the ground that (1)
it is ‘not true modal but no discussion of must or of the modals of obligation and necessity
would be complete without reference to it.’ (Coates, 1983: 52) and (2) it is the most common
form in both American English and British English according to Mairs’ (2006) investigation
into modal frequency. Though dare and had better are semi-modals, they are excluded from
this list since dare is ‘rare and apparently on the decline’ (Coates, 1983: 5) and had better is
‘actually declining’ (Leech 2003: 229). Note that in the English corpus of this study, there is
no occurrence of dare and had better. Thus, dare and had better are intentionally ignored in

this study, but need to is discussed in Chapter III & IV, because the analysis of the modals of
obligation and necessity is not adequate without it and the use of need to is increasing
especially in American English (cf. Mairs 2006). Also, the usages of will, would and shall that
express pure tense or mood will be disregarded in this study. Ought to is sometimes considered
as a maginal case, but apart from the to-infinitive, it presents no problem with the formal
charateristics of a modal auxiliary verb.
With respect to Vietnamese, studies conducted by some researchers such as C.X.Hạo (1997,
2004), N.V.Hiệp (2007, 2009); D.Q.Ban & H.Dân (2000), D.Q.Ban & H.V.Thung (2012),
N.T.Thìn (2003), Đ.H.Châu (1996), Đ.H.Châu & B.M. Toán (2001), V.Đ.Quang (2008),
N.T.Thuận (2003), N.T.Hùng (1994), N.T.Hùng (2002, 2003), V.Đ.Nghiệu (1998), B.T.Ngoãn
(2002, 2003), H.V.Thông (2001), P.T.T.Thùy (2008), N.T.T.Thuỷ (2011, 2012), B.T.Đào
(2014) show that modality in Vietnamese language can be expressed by different linguistic
expressions, such as modal verbs (nên, cần, phải, có thể, sẽ, etc.); epistemic lexical verbs (tin,
đoán, nghĩ, đồ, etc.); modal adjectives (chắc, đúng, etc.); modal adverbs or modal set
expressions (có lẽ, dường như, có khi, biết đâu, etc.); modal nouns (khả năng, tin đồn, etc.);
and modal particles (như, nhỉ, đấy, chứ, à, á, ạ, etc.). It is almost impossible to discuss all
these types of Vietnamese modal expressions within the scope of this study. Moreover,
P.T.T.Thùy’s PhD dissertation (2008), and N.T.T.Thuỷ’s survey (2012) show that Vietnamese
modal verbs are considered as the most frequent modal expressions in academic writing.
Therefore, the study is limited to discuss and analyse root and epistemic modality as realized
by Vietnamese modal verbs such as nên, cần, phải, có thể, sẽ, định, muốn, toan, dám, with
examples mainly taken from the 500, 000-word corpus of 119 Vietnamese social science texts.
3
The main claim here is that (1) these Vietnamese modals seem to be equivalent of the above
English modals; (2) by referring to other scholars’ research such as N.K.Thản (1999: 174-178);
D.Q.Ban & H.Dân (2000: 57-58), D.Q.Ban & H.V.Thung (2012: 104-105), N.T.Thuận (2003:
30-31), P.T.T.Thùy (2008), V.Đ.Quang (2008), B.T.Ngoãn (2002, 2003), B.T. Đào (2014) the
researcher can identify and categorize root and epistemic senses of modal verbs; and (3) the
reseacher has to synthesize and analyze different meanings of modal verbs.
In this study, the Cognitive Linguistics (CL) is considered as a theoretical framework since the

CL account “differs radically from traditional perspective by emphasizing that language is a
reflection of general cognitive processes, not a separated/ isolated system with its own systems
of rules” (Tyler, 2008: 459-60). In comparison with formal approaches, CL “stands out by
resisting the imposition of boundaries between language and other psychological phenomena.
… Rather than a distinct, self-contained entity (separate “module” or “mental faculty”),
language is viewed as an integral facet of cognition” (Langacker, 2013: 7-8). Cognitive
Linguistics is “an approach to language that is based on experience of the world and the way
we perceive and conceptualize it.” (Ungerer & Schmid, 1996: xxi). The foundational point of
CL ‘is simply that language is all about meaning.’ (Depraetere & Reed, 2006: 3)
Some Cognitive researchers such as Mortelmans (2007: 881) argue that ‘the cognitive
linguistic concepts of force dynamics, …. have proved to be highly powerful tools to discover
common cores in a wide variety of modal expression types’. Therefore, the researcher based
on the notions of force dynamics (opposition) proposed by Talmy (1988, 2000ab, 2003);
Langacker (1991ab, 2003, 2008, 2013); Sweetzer (1990); Johnson (1987); Taylor (2002);
Pelyvás (1996, 2003, 2006, 2008) to discuss and analyse the root and epistemic senses of
English and Vietnamese modal verbs.
The data submitted to the English and Vietnamese root and epistemic modality are mostly
taken from the two corpora: one in English and the other in Vietnamese. With the help of the
corpus-based analysis - the TexSTAT-2 programme, the study seeks to find the frequency and
KWIC (Key Word In Context) concordance of English and Vietnamese modal auxiliary verbs.
Moreover, string matching of each modal verb in English and Vietnamese social science texts
is illustrated in Appendix C, pp. XXXIII - LXIV of the study.
The main emphasis of the study is to explore the equivalence and non-equivalence of root and
epistemic senses of modal verbs between English and Vietnamese languages in terms of force
dynamic analyses. However, it cannot be said that all English and Vietnamese social science
4
texts share such similarities and differences in every context. And finally, the study puts
emphasis on some major findings, their implications and gives some suggestions for avoidance
and for further research.
To a large extent, the study does not mention the following issues: (1) The mood system,

which deals with the syntactic structure of the sentence and not necessarily with what the
speaker is doing and which consists of indicatives, imperatives and subjunctives; (2) Other
types of modal expressions such as modal adjectives, modal nouns, hedging devices, modal
adverbs, modal particles; and (3) The intonation or prosodic features as the focus of the study
is on written texts. However, they will be dealt with or touched if necessary.
1.3. Aim and Objectives of the Study
The ultimate aim of the study to show how force dynamics framework is used as a powerful
tool to describe, analyze and compare/contrast modality in English and Vietnamese in order to
find the similarities and differences between English and Vietnamese modality as realized by
modal verbs so that it can help improve improve teaching and learning English in Vietnamese
context.
Therefore, the objectives of the study are:
- to identify and describe root and epistemic modality as realised by modal verbs in English
and Vietnamese from the Cognitive perspective, more specifically in terms of force
dynamics;
- to find the similarities and differences between English and Vietnamese root and
epistemic modality as realised by modal verbs from force dynamics frameworks.
1.4. Research Questions
In order to achieve the above aim and objectives, the study seeks to answer the following
research questions:
1. How are root and epistemic senses of modality as realized by modal verbs in English
and Vietnamese in terms of force dynamics?
2. What are the similarities and differences between English and Vietnamese root and
epistemic modality as realized by modal verbs from force dynamics perspective with
reference to the frequency occurrences of modal verbs?
5
1.5. Methods of the Study
The study is aiming at comparing/ contrasting English and Vietnamese root and epistemic
senses of modal verbs in terms of force dynamics. Therefore, the principal method applied for
the study is the contrastive analysis (CA), which is defined by Richards et al. (1992: 83) as ‘the

comparison of the linguistic system of two languages’. During the comparison and contrast,
English is considered as the source language and Vietnamese as a language of reference.
Therefore, in this study, it is assumed that the notions of force dynamics are first used to
describe and analyse root and epistemic modality realized by English modals and then they
will be adapted to deal with those of the Vietnamese language.
The study was also conducted with the help of corpus-aided analysis of English and
Vietnamese social science texts in order to find out the frequency and KWIC (key word in
context) concordance of a certain modal verb. The analysis of the study is undertaken by
blending the quantitative research approach with the more qualitative research approach. The
quantitative approach gives a statistical overview of large amounts of the texts in question -
more precisely, large numbers of tokens of the English and Vietnamese modal verbs in the
authentic social science texts in the two corpora (a 500 000 - word corpus in English and a
500000 - word corpus in Vietnamese), whereas the qualitative one refers to the close, detailed
examination of particular stretches of the modal verbs in terms of forces and barriers. It may be
possible to better understand the processes at play in the texts and to gain access to non-
obvious meanings of the key words.
The study is an attempt to contribute to the application of the Cognitive linguistics as a
theoretical background to compare/ contrast the two languages: English and Vietnamese in
terms of modality expressed in authentic social science texts on the ground that: (1) Language
is claimed to be best studied and described with reference to its cognitive, experiential and
social contexts. (Kemmer, 2000); (2) Cognitive linguistics ‘highlights recurrent, meaningful
linguistic patterns and organising principles found at all “levels” of language’ (Tyler 2008:
461); and (3) Language has ‘two basic and closedly related functions: a semiological function,
allowing thoughts to be symbolized by means of sounds, gestures, or writing as well as
interactive function …” (Langacker, 1998: 1).
With respect to corpus-based research in this study, it is argued by some researchers such as
Gonzales-Marquez et al. (2007: 149) that “Cognitive linguistics considers itself to be a non-
objectivist theory of language, whereas the use of corpus materials involves an attempt to
6
maximalize the objective basis of linguistic descriptions”. According to them, there are two

compelling reasons for Cognitive linguistics to embrace corpus research: (1) The growing
tendency in Cognitive linguistics is assumed to stress its essential nature as a usage-based
linguistics. We cannot have usage-based linguistics unless we study actual usage – as it
appears in corpora in the form of spontaneous, non-elicited language data, and (2) the very
emphasis that Cognitive linguistics places on the fact that our knowledge of the world is an
active construal rather than a passive reflection of an objectively given world, favours an
interest in differences of construal between cultures, social groups, or even individuals. (ibid.)
Contextual analysis of authentic social science texts was also done in order to identify the
purposes and meanings of modal verbs in a particular case. Since the two said corpora are not
so large, a close reading of the whole texts could be undertaken. This is useful because it
allows a more detailed look at the authentic materials, taking into considerations single words
as well as strings of words and their collocations. The purpose of this level of analysis is to
take into account root and epistemic senses realized by different modal verbs used in different
contexts.
Moreover, it is necessary for the researcher to consult supervisors, other researchers and
colleagues with a view to accomplishing and improving the quality of the study. It is also
important to state that the above methods are not conducted isolatedly but interactively and
cooperatively.
As stated above, the study does not concern the following issues: the mood system; modal
adjectives, modal nouns, hedging devices, modal adverbs, modal particles; the intonation or
other prosodic features. However, they will be dealt with or touched when necessary.
1.6. Contribution of the Study
1.6.1. Theoretical Significance of the Study
The study hopes to make a contribution to
The development of the Cognitive perspective to describe and analyze an interesting, but
complicated language phenomenon, i.e. modality in general, and modal verbs in particular, in
two languages: English and Vietnamese;
The development of the corpus-aided approach to find out the frequency and collocations
of modal verbs appearingin English and Vietnamese social science texts;
The development of the contrastive and comparative analysis of English and Vietnamese

modality from Cognitive perspective, more specifically, in term of force dynamics.
7
1.6.2. Practical Significance of the Study
The study wishes:
to provide a systematic description and analysis of modals in English and Vietnamese in
terms of force dynamics;
to assist writers who are not native speakers but who are seeking to publish their research
papers in English journals;
to discover what lies behind the differences in modality between English and Vietnamese
in order to raise awareness as well as interest in learning and teaching foreign languages in a
way that one should take the social and cultural differences between one’s mother tongue and
his/ her target language into consideration.
1.7. Structure of the Dissertation: Apart from the introduction and conclusion, the study
consists of 4 chapters:
Chapter I first presents a brief discussion of the concept of modality from traditional point of
view. Then it investigates the two main types of modality: root and epistemic modality. Next,
an overview of Cognitive linguistics is presented, which serves as a theoretical background.
And lastly, it provides force dynamic frameworks of modal verbs.
Chapter II starts with restating the research questions. Then, it describes the principal method
of the study, the data collection, the corpus-aided analysis and the Cognitive analysis
framework.
Chapter III concentrates on the contrastive/ comparative analysis of root senses of modal verbs
in English and Vietnamese. It intends to find the similarities and differences between English
and Vietnamese modality in the expression of obligation, permission, ability and volition in
terms of force dynamics with reference to frequency occurrences of English and Vietnamese
modal verbs, respectively.
Chapter IV focuses on finding the similarities and differences between English and
Vietnamese epistemic modality (with regard to necessity, probability and possibility) realised
by modal verbs in terms force dynamics with reference to frequency of English and
Vietnamese modal verbs. In chapter three & four, the analysis of root and epistemic senses of

modals will be done together with the corpus-based analysis of English modals in the English
corpus and Vietnamese modals in the Vietnamese corpus. String matching of each modal verb
in the English and Vietnamese corpus will be illustrated in accordance with KWIC (Key
Words In Context) concordance.
8
PART TWO: DEVELOPMENT
Chapter I: Literature Review
1.1. Introduction
This chapter aims to discuss the wide-ranging literature on modality, and distills the notions
and categories that are useful to the present study of constrasting/ comparing root and
epistemic modality realised by modal verbs found in English and Vietnamese social science
articles in terms of force dynamics from Cognitive perspective. The literature on modality has
typically concentrated on the category of modal verbs, with the English modal auxiliaries as
the prototypical cases (or as the source) and the Vietnamese modal verbs as the comparative
ones. This bias can be found both in language-specific accounts (e.g. Palmer 1990, Coates
1983, Sweetser 1990, Johnson 1987, Taylor 2002, Talmy 2000a, Langacker 1991b, 1999,
Huddleston 1984, Downing & Locke 1992) and in cross-linguistic studies (e.g. Palmer 1986,
Bybee, Perkins and Pagliuca 1994), although lately some linguists have taken a broader
perspective, like Nuyts (2001) on epistemic modality, and Linden (2012) on modal adjectives.
This chapter begins with describing and analysing the concept of modality, types and
meanings of modality from traditional point of view. It is due to the fact that the semantic
category of modality is not as easily defined as tense or aspect (Bybee, Perkins & Pagluica
1994: 176) and “modality and its types can be defined and named in various ways,” and that
“there is no one correct way” (Van der Auvera and Plungian, 1998, cited in Mortemans, 2007:
869). Then it will present an overview of the Cognitive perspective. And lastly, it provides
force dynamic frameworks of root and epistemic senses of modal verbs in English and
Vietnamese.
1.2. Modality from the Traditional Point of View
1.2.1. The Concept of Modality
Traditionally, the concept of modality and the modal concepts of possibility, probability and

necessity, according to Hoye (1997), go back to Aristotle and classical Greek philosophy.
These notions seem to derive from the fact that human beings often categorize their attitudes
and experiences in terms of the ways things might or must be or might have been, other than
they actually are or were. Therefore, this part gives a summary of some authors’ point of views
of modality such as Jesperson (1949), von Wright (1951), Rescher (1968), Bybee (1985),
McCarthy (1994), Lyons (1977) and Palmer (1986).
9
According to Jesperson (1949, cited in N. Hòa, 2004: 175), modality is defined as ‘an
interesting issue, which can be divided into two kinds: the first contains an element of will,
which corresponds to deontic modality and the second contains no element of will, i.e.
epistemic modality’. Although Jesperson’s proposals of two types are of great importance,
they contain little theoretical significance. They are purely notional, and both of his choice of
the sub-categories and his criteria for them may be seriously questioned (cf. Palmer, 1986).
Von Wright (1951, cited in Palmer, 1986) in a pioneering work on modal logic classifies four
different ‘modes’: (1) the alethic mode or modes of truth; (2) the epistemic modes or modes of
knowing; (3) the deontic modes or modes of obligation and (4) the existential modes or modes
of existence. The most important distinction here is that between epistemic and deontic
modality, which correspond, very roughly, to Jesperson’s two types.
Within a logical framework, Rescher (1968) proposes a more extended modality system which
consists of not only ‘elethic’ modalities relating to the notion of truth value, ‘epistemic’
modalities relating to knowledge and belief, ‘deontic’ modalities relating to duties, but also
‘temporal’ modalities, ‘boulomaic’ modalities, ‘evaluative’ modalities, ‘likelihood’ modalities
and ‘causal’ modalities. He further argues for three types of ‘conditional’ modality. According
to Rescher (1968: 24-6), ‘A proposition is presented by a complete, self-contained statement
which taken as a whole, will be true or false’. He then continues, “When such a proposition is
itself made subject to some further qualification of such a kind that the entire resulting
complex is itself once again a proposition, then this qualification is said to represent a
modality to which the original proposition is subjected.” Palmer (1986) argues that Rescher’s
definition of modality would raise serious theoretical problems and would be too wide.
Perkins (1980) establishes his classification of the types of modality by reference to Rescher’s

conceptual domain of modality. He reduces Rescher’s eight categories to four: epistemic
modality which is defined in terms of rational laws; deontic modality which is defined in terms
of social laws; dynamic modality defined in terms of natural laws and temporal modality.
Searle’s (1979) approach to modality is different from the above discussions. He concerns the
issues of modality in terms of speech act theory. According to him, there are five categories of
illocutionary acts: (1) assertives: where we tell our hearers how things are; (2) directives:
where we get them to do things; (3) commisives: where we commit ourselves to doing things;
(4) declaration: where we bring about changes in the world with our utterances; and (5)
expressives: where we express our feelings and attitudes. While assertives are described in
10
terms of the speaker’s belief or commitment to the truth of a proposition, directives and
commissives correspond very largely to deontic modality. Commissives are speaker-oriented
whereas directives are hearer-oriented. Declaratives come close to assertives and therefore
they are connected to epistemic modality. Expressives may belong to epistemic modality.
Modality, in Bybee’s point of view (1985), in a broad sense is what the speaker is doing with
the whole proposition whereas modality in Pamper’s (1986) view point is defined as semantic
information associated with the speaker’s attitude or opinion about what s/he says. (Cited in N.
Hòa, 2004).
McCarthy (1994: 94) defines “modality as a kind of thought often consisting of the closed
class of modal verbs (must, can, will, may, etc.) and being treated as part of grammar of
English, but a large number of lexical words (nouns, adjectives, verbs, and adverbs) carry the
same or similar meanings to the modal verbs”.
Lyons (1977) recognizes two kinds of modality using von Wright’s terms: Epistemic modality
and deontic modality. While the term ‘epistemic’ coming from a Greek word meaning
“knowledge” is concerned with matters of knowledge, belief or opinion rather than fact, the
term ‘deontic’ coming from a Greek word relating to the imposition of obligations is
concerned with the necessity or possibility of acts performed by morally responsible agents.
Modality is claimed to express subjectivity of the speaker (Lyons, 1977; Palmer, 1986).
However, Palmer (1986) argues that it is not possible to decide whether modals are subjective
or not, as in ‘You must leave at once’. This sentence can indicate that it is the speaker’s

insistence or general (objective) necessity for leaving, or it is indeterminate between the two
readings. It is in principle not possible to justify the one interpretation rather than the other.
Therefore, it needs a specific context to clarify its meaning. ‘You must leave at once’ could be
construed in an alternative analysis, i.e., in terms of force dynamics from Cognitive
perspective.
The definition of modality applied in this study is used most widely, agreeing with the view of
Lyons (1977: 452), i.e. modality is defined as “the speaker’s opinion or attitude toward the
proposition that sentence expresses or the situation that the proposition describes.’ Moreover,
the study mainly follows the narrow definition of modality defined by Lock (1996: 193), i.e.
“A narrow definition of modality encompasses only modal auxiliaries and their uses ” For
the purpose of the study, modality will be considered as a semantic system expressed by the
modal verbs which enable a speaker/ conceptualizer to signal and express his/ her own point of
11
view, his/ her opinion or his/ her commitment to the truth of the proposition/ state of affair or
the event.
When modality is treated as a purely logical notion, it concerns logical possibility and
necessity. In these logical discussions, one finds inquiries into the nature of terms such as
“possible” and “necessity” in statements of the following sort: “It is necessary that p = it is
impossible that not - p = it is not possible that not - p,” and, “It is necessary that not - p = it is
impossible that p = it is not possible that p” (Johnson, 1987: 48-49).
In contrast with this logical analysis of modality, there are “other senses of modal verbs that
are intimately related to our everyday experience, insofar as they represent our pervasive
experience of things, events and relations as being actual, possible or necessary”. (Johnson
1987: 49). Together with Johnson (1987), some cognitive linguists such as Talmy (1988,
2000a & b), Sweetser (1990), Taylor (2002), Langacker (1990, 1991a, 1991b, 1999, 2003)
developed an alternative analysis of semantics of modals based on force dynamic frameworks.
Therefore, modals in this study “are grammaticized grounding elements, in which the ground -
the speech event and its participants - are ‘offstage’ and subjectively construed’ (Langacker
2003: 3), and have ‘two crucial properties: (1) they are force- dynamic and (2) the event
marked by the complement remains potential rather than actual.’ (Langacker 1999: 308). The

force dynamics are ‘inherent in the conceptualizer’s mental activity, hence subjectively
construed in the strong sense.’ (ibid.)
In what follows, the researcher will demonstrate the description and analysis of English and
Vietnamese modality as realized by modal verbs from Cognitive perspective, more specifically
in terms of force dynamics.
1.2.2. Types of Modality
In this section, some main types of modality such as epistemic modality vs. deontic modality;
root modality vs. epistemic modality; agent-oriented modality vs. speaker-oriented modality;
extrinsic modality vs. intrinsic modality will be discussed with reference to some researchers
including Bybee & Fleischman (1995), N.V. Hiệp (2009), Palmer (1986, 1990), Nuyts (2001,
2006), Coates (1983), Bybee et al. (1994), Biber et al. (1999), Perkins (1980, 1983),
Huddleston (1980), Linden (2012), Declerck (2011), Johnson (1987), Talmy (1988, 2000ab),
Sweetser (1990), Taylor (2002), and Langacker (1990, 1991ab, 1999, 2003).
12
1.2.2.1. Agent-oriented Modality vs. Speaker-oriented Modality
Agent-oriented modality applies to ‘all modalities in which conditions are predicated on an
agent (obligation, desire, ability, permission and root possibility)’ (Bybee & Fleischman, 1995:
5) while speaker-oriented modality applies to a whole proposition and communicates the
speaker's stance concerning its truth (Palmer, 1990). Agent-oriented modality can be expressed
by lexical or grammatical morphemes. Some of the most semantically specific notions in this
set include necessity, ability, desire and obligation as in [1.1]:
[1.1] All students must obtain the consent of the Dean of the falculty concerned before
entering for exam (Root – obligation) (Coates 1983: 35)
While ‘agent-oriented modality reports the existence of internal and external conditions on an
agent’ (Bybee et al. 1994: 179), speaker-oriented modalities allow the speaker to impose such
conditions on the addressee. (ibid.) The grammatical terms for speaker-oriented modality may
encompass imperative (the form used to issue a direct command), prohibitive (a negative
command), optative (the wish or hope of the speaker in a main clause), hortative (the speaker
is encouraging someone to action), admonitive (the speaker is issuing a warning) and
permissive (the speaker is granting permission) (ibid.). Speaker-oriented modality is meant to

include directives as well as utterances in which the speaker grants the addressee permission as
in [1.2]
[1.2] You can start the revels now. (Root – ability) (Coates 1983: 88)
1.2.2.2. Extrinsic Modality vs Intrinsic Modality
Extrinsic modality refers to extra-propositional modality, expressing the speaker's attitude
towards the content of a proposition. It covers the area of epistemic modality. For Biber et al.
(1999: 485) it "refers to the logical status of events or states, usually relating to assessments of
likelihood: possibility, necessity, or prediction" and is synonymous with epistemic modality.
However, intrinsic modality forms part of the semantic content of the proposition; it covers the
area of root modality. Biber et al. (1999) do point out that each modal has both intrinsic and
extrinsic modality. While ‘intrinsic modality refers to actions and events that humans (or other
agents) directly control: meanings relating to permission, obligation, or volition (or intention)"
and is synonymous with deontic modality, “extrinsic modality refers to logical status of events
or states” (Biber et al. 1999: 485).
13
1.2.2.3. Deontic Modality, Dynamic Modality and Epistemic Modality
Some scholars such as Nuyts (2001) states that modality usually covers three categories of
qualifications: deontic (root) modality, epistemic modality, dynamic modality. Traditionally,
deontic modality has been defined in terms of the concepts of permission and obligation: in
their deontic meanings, the verbs like must express obligation to carry out a certain activity/
task, as in [1.3]
[1.3] In culturally competent practice with other groups, social workers must develop the
skills, values and knowledge for working with a diverse population. (Deontic - obligation)
(ESoci 1)
while the verbs like may express permission to do it (cf. Lyons 1977; Palmer 1990), as in
[1.4],
[1.4] … Women may resist this practice by having an extramarital affair or getting a
divorce, options not easily available to women in Laos, due to the economic and cultural
constraints. (Deontic – permission) (EEdu 15)
Closedly related to deontic modality, according to Simpson (1993: 48), is boulomaic modality,

which is ‘extensively grammaticalized in English in expressions of ‘desire’. Palmer (1986)
states that the most important types of deontic modality in a grammatical study appear to be
Directives (‘where we try to get our hearers to do things’ (Searle 1983)) and Commissives
(‘where we commit ourselves to do something’ (Searle 1979)). Both of them are not only
subjective, but also performative as they actually initiate action by others or by the speaker.
However, as Palmer (1986) observed, there are problems with subjectivity in the analysis of
deontic modality, in that some deontic uses of modals seem to have no elements of subjectivity
whereas others seem to include varying degrees of the speaker’s involvement.
Epistemic Modality
The term ‘epistemic modality’ is to apply not simply to modal system that basically involves
the notions of possibility and necessity, but to any model system that indicates the degree of
commitment by the speaker to what he says. It is to be interpreted as showing the status of the
speaker’s understanding or knowledge; this clearly includes both his own judgements and the
kind of warrant he has for what he says (Palmer, 1986). And it should include evidentials
(ibid.). While there is still some controversy existing on whether or how evidentiality is to be
included within the epistemic domain, it is agreed by some authors such as Nuyts (2001) that
evidential modality indicates the source of information on which the speaker draws to make a
statement about the existence of state of affair (SoA).
14