Editing Otto Jespersen (section)

==Academic life and work==
Jespersen entered the [[University of Copenhagen]] in 1877 when he was 17, initially studying law but not forgetting his language studies.<ref name="warwick">{{Cite web|first=Richard C. | last=Smith | url=http://www2.warwick.ac.uk/fac/soc/al/research/collect/elt_archive/halloffame/jespersen/life|title = Otto Jespersen's life and career | website=Applied Linguistics | publisher=University of Warwick | year=2007}}</ref> in his first year at university, he attended a lecture course by {{ill|Sophus Heegaard|da||sv|}} on the history of [[Evolutionism]] since the Greeks; this introduced him to the ideas of [[Herbert Spencer]], and later in life he looked back on the course warmly.{{Sfnp|Nielsen|1989b|p=13}} Jespersen taught languages in a lower secondary school,{{Sfnp|Kabell|2000|p=30}} and from 1880 to 1887 was a stenographer for the [[Rigsdagen|Rigsdag]] (Danish parliament). The income from these allowed him in 1881 to shift his focus completely to languages.<ref name="leksikon" /> Following the introduction of a new degree, ''Skoleembedseksamen'', Jespersen switched to this, choosing [[French language|French]] as the major subject and English as the second minor subject, the first compulsorily being [[Latin]]. He was one of a large number of students who appealed for Latin to be made voluntary, but the appeal was unsuccessful.{{Sfnp|Nielsen|1989b|pp=15–16}} Jespersen studied under [[Karl Verner]], [[Hermann Möller]] and particularly [[Vilhelm Thomsen]] among linguists; and more broadly, under [[Harald Høffding]]: it was thanks to Høffding that Jespersen was further exposed to the writings and ideas of [[Charles Darwin|Darwin]], [[John Stuart Mill|Mill]] and [[Herbert Spencer|Spencer]], and to introspective psychology.{{sfnp|Hjelmslev|1943|pp=119–120}}

In 1887 he passed ''Skoleembedseksamen''. For French, he chose to be examined on [[Denis Diderot|Diderot]], reflecting a lasting enthusiasm for the ideals of the [[French Revolution]] and the [[Age of Enlightenment]].  Throughout his life Jespersen remained faithful to the ideals and methods of his early teachers. Positivist and evolutionary attitudes, physiological and psychological methods in their classical form, and finally, liberal humanism were essential to his character.{{sfnp|Hjelmslev|1943|pp=119–120}}

Jespersen's views on language owed less to theoretical considerations than to a practical and thus largely functional conception of language; as a language theorist, Jespersen could remain tethered to reality thanks to the common sense fundamental to his character. Even when making such bold proposals as that of the "progress" of a language, he could avoid extremes.{{sfnp|Hjelmslev|1943|p=121}}

In 1887–1888, he traveled to England, Germany and France, meeting linguists like [[Henry Sweet]] and [[Paul Passy]] and attending lectures at institutions such as [[University of Oxford|Oxford University]].{{Citation needed|date=May 2025}} Following a tip from his mentor [[Vilhelm Thomsen]] that not many years would pass before there would be a vacancy for a specialist in English, he returned to Copenhagen in August 1888 and began work on his doctoral dissertation on the English [[Grammatical case|case]] system, which he defended in 1891. His doctorate entitled Jespersen to teach in the university without pay as a ''Privatdocent''; he took this opportunity to teach classes on [[Geoffrey Chaucer|Chaucer]] and [[Old English]], thereby adding to his qualifications for the post; he also wrote a book on Chaucer.{{Sfnp|Nielsen|1989b|pp=16–17}} 

On the resignation of [[George Stephens (philologist)|George Stephens]] as ''Docent'', his newly vacant post was upgraded to that of Professorship of English language and literature. Jespersen was one of four applicants; the others were {{Ill|Adolf Hansen|da|Adolf Hansen (litteraturhistoriker)}} and [[Jón Stefánsson (academic)|Jón Stefánsson]] (both rather lacklustre), and [[William Craigie]] (then very young).{{Sfnp|Nielsen|1989b|pp=17–18}} This was "a no-holds-barred contest", during which Jón Stefánsson even published a book{{Efn|1={{Cite book | author=Jón Stefánsson | title=Dr. O. Jespersen på Krigsstien | trans-title=Dr. O. Jespersen on the warpath | location=Copenhagen | publisher=Gad | year=1893 | oclc=463247253 | language=da}}}} charging Jespersen with plagiarizing [[Georg von der Gabelentz]]. (Gabelentz himself denied this.){{Sfnp|McElvenny|2017|loc=p.&nbsp;424 n.&nbsp;36}} Up to date in English philology, familiar with English literature, and "[speaking] English perfectly", Jespersen was chosen.{{Sfnp|Nielsen|1989b|pp=17–18}} 

Jespersen was a professor of English at the University of Copenhagen from 1893 to his retirement in 1925. This was not such a comfortable position: in 1911 he published an article in the newspaper ''[[Politiken]]''{{Efn|1={{Cite newspaper | first=Otto | last=Jespersen | title=Videnskabens kår | trans-title=The state of science | newspaper=Politiken | date=13 May 1911 | language=da}}}} describing poor conditions for academic work (serious underfunding, and the lack of a compulsory retirement age for professors), and also how he had got his wife to promise to shoot him if he failed to retire at 65.{{Sfnp|Nielsen|1989b|pp=19–20}} He remained something of a radical, in a magazine article published in 1914{{Efn|1={{Cite magazine | first=Otto | last=Jespersen | title=Universitetsønsker | trans-title=University aspirations | magazine=[[Tilskueren]] | year=1914 | pages=124–133 | language=da}}}} he made further recommendations: that Denmark should have more than one university (its second would only arrive in 1928), that a Faculty of Divinity did not belong in a modern university, that there should be financial incentives for students to proceed to postgraduate work, and more. However, although Jespersen succeeded in having Latin removed as a compulsory minor, it can be inferred{{Efn|1="[I]t seems easy to see Jespersen's hand" in the new status of Chaucer; "the Jespersen who created three sacred cows (Chaucer, Spenser and Milton) to join Shakespeare".{{Sfnp|Nielsen|1989b|p=23}}}} that he backed the compulsory inclusion of [[William Chaucer|Chaucer]], [[Edmund Spenser|Spenser]] and [[John Milton|Milton]] in the English course.{{Sfnp|Nielsen|1989b|pp=22–23}}

Jespersen was Dean of the Faculty of Arts from November 1904 to November 1906; and [[Rector_(academia)#Denmark|Rector]] (vice-chancellor, or president) of the university from November 1920 to November 1921. Among his engagements while Rector was an address at the inauguration in March 1921 of the Institute of Theoretical Physics (later renamed [[Niels Bohr Institute]]). Another was a speech{{Efn|1=Reprinted in {{Cite book | chapter= | trans-chapter= | first=Otto | last=Jespersen | title=Tanker og studier | trans-title=Thoughts and studies |  location=Copenhagen | publisher=Gyldendalske Boghandel | year=1932 | pages=18–26 | oclc=1508095448 | language=da}}}} welcoming new students in September 1921 "he exhorts [them] to absorb the scholarly and scientific tradition (to the extent of being critical of their professors!), the only genuine hallmark of academics".{{Sfnp|Nielsen|1989b|pp=21–22}} 

Jespersen's early work focused primarily on language teaching reform and on phonetics, but he is better known for his later work on syntax and on language development.

===Language teaching===
At the end of the 19th century the teaching in Denmark of contemporaneous foreign languages was ossified, and very similar to that of long-dead classical languages. This was despite the belief of {{Ill|Niels Matthias Petersen|lt=N.&nbsp;M. Petersen|da||de||fr||sv}}, expressed decades earlier, that pupils should be encouraged to acquire a second language as they had acquired their first, and indeed despite the writings of [[Jan Amos Comenius]] in the 17th century.{{Sfnp|Sørensen|1989|p=34}}

In 1886, Jespersen, {{Ill|August Western|no}} and [[Johan August Lundell]] cofounded a Scandinavian group for a revitalization of language teaching, naming the group "Quousque Tandem" after [[Wilhelm Viëtor]]'s pseudonym as author of the 1882 pamphlet ''Der Sprachunterricht muss umkehren!'' ("Language teaching must start afresh!").{{Efn|1=The second edition (1886) – whose title page incidentally identifies "Quousque Tandem" as "Wilhelm Vietor" (without [[Diaeresis (diacritic)|diaeresis]]) – is [https://archive.org/details/dersprachunterr00vigoog/page/n5/mode/2up here] at the Internet Archive.}} The group opposed the use of [[Grammar–translation method|theoretical grammar and translation exercises]], advocating in its place the teaching of a language in its spoken and living form by the [[Direct method (education)|"direct" method]], informed by phonetics. As a campaigner, he was an extremist: [[Louis Hjelmslev|Hjelmslev]] writes that this was an area where Jespersen's normal moderation and common sense were counterbalanced by a revolutionary fervour, and that he was a "[[Jacobins|Jacobin]]" among linguists.{{sfnp|Hjelmslev|1943|pp=121–122}}

Jespersen's first book (1884) was a Danish translation, ''Praktisk tilegnelse af fremmede sprog'' ("Practical acquisition of foreign languages"), of ''Die praktische Spracherlernung'',{{Sfnp|Nielsen|1989b|p=15}} by Felix Franke. Both Franke (also born in 1860) and Jespersen first assumed that the other was much older than himself, but from its start in 1884 their correspondence quickly became a lively discussion (about two hundred letters and postcards survive) of such matters as second language education and phonetic scripts; it was cut short in 1886 when Franke succumbed to tuberculosis.{{Sfnp|Kabell|2000}}{{Efn|1=For a short biography of Franke, see Frank-Rutger Hausmann, "[https://gams.uni-graz.at/o:hsa.person.1512 Felix Franke]" (2022), {{hdl|11471/518.10.2.1512}}; in Bernhard Hurch, ed., ''Hugo Schuchardt Archiv'', [[University of Graz]].}}

In an article published in 1886{{Efn|1={{Cite magazine | first=Otto | last=Jespersen | title=Den nye sprogundervisnings program | trans-title=The new language teaching programme | magazine=Vor ungdom | year=1886 | pages=353–381 | language=da}}}} (and elaborated in his 1901 book ''Sprogundervisning'', translated as ''How to teach a foreign language'', 1904), Jespersen argued for the following principles in language teaching:
# Teaching should be based on spoken rather than written language. To this end, at early stages of language teaching, only a phonetic script should be used, and this script should be clear and precise.
# Material for reading should not consist of unrelated sentences. It should instead constitute coherent texts, preferably designed so that the meanings of unfamiliar words can be inferred from their contexts.
# At early stages the teaching of grammar should be minimized, and the pupils encouraged to infer grammatical patterns for themselves. Grammar may be examined and practised later, but time should not be spent on grammatical curios, and form and function should not be separated.
# Exercises in translating the second language into the first should not be emphasized; exercises in translating the first into the second are of very little utility.{{Sfnp|Sørensen|1989|pp=35–38}}

Jespersen followed his 1884 translation of Franke with ''Kortfattet Engelsk grammatik for tale- og skriftsproget'' (1885), ''Fransk læsebog efter lydskriftsmetoden'' (1889), and (with {{Ill|Christian Sarauw|da|Christian Sarauw (sprogforsker)|sv|Christian Sarauw (språkforskare)}}) ''Engelsk begynderbog'' (1895): books which, together with those written by others that similarly used the "[[Direct method (education)|direct method]]", soon took over from the "[[Grammar–translation method|grammar–translation]]" material against which Jespersen and Quousque Tandem had rebelled.{{Sfnp|Sørensen|1989|p=38}}

===Phonetics===
Jespersen's interest in phonetics was prompted by [[Henry Sweet]]'s ''Handbook of Phonetics'' (1877), and the lectures of [[Vilhelm Thomsen]].{{Sfnp|Rischel|1989|p=46}} In the 1880s, inspired by [[Alexander Melville Bell|Melville Bell]] and other British phoneticians, he developed what he first called an "analphabetic" system{{Efn|1=Published in ''The Articulations of Speech Sounds Represented by Means of Analphabetic Symbols''}} – which, "to avoid ridicule", he later termed an "antalphabetic" system – that used a series of three variables for any [[Phone (phonetics)|phone]]: lowercase Roman for the passive [[Articulatory phonetics#Articulators|articulator]], lowercase Greek for the active articulator, and numerals and more for "the degree and shape of the aperture at a place of constriction". [[Jørgen Rischel]] points out that a given "anatomical feature" can be labelled according to its use: thus rather than simply "uvular", the role of the [[uvula]] can be described as "a passive articulator in [[uvular consonant]]s but an active articulator in [[Nasalization|nasalized]] sounds".{{Sfnp|Rischel|1989|pp=48–49}}

In June 1886, he became a member of the [[International Phonetic Association]] (IPA), then called the Phonetic Teachers' Association. The idea of creating a phonetic alphabet that could be used by every language was first put forward by Jespersen in a letter he sent to [[Paul Passy]].<ref name="principles">{{Cite journal|title = The Principles of the International Phonetic Association: 1949| journal=Journal of the International Phonetic Association | orig-date=1949 | year=2010 | volume=40 | issue=3 | pages=299–358 | jstor=44526579}} In a supplement on the cover, "A short history of the Association Phonétique Internationale".</ref> Jespersen's transcription system for English, used in {{Ill|John Brynildsen|no}}'s ''Engelsk–Dansk–Norsk Ordbog'' = ''A Dictionary of the English and Dano-Norwegian Languages'' (1902–1907), is very close to that of [[Daniel Jones (phonetician)|Daniel Jones]], which it preceded by some years.{{sfnp|Basbøll|2021|pp=539–540}} Language-specific systems were not unusual at the time ([[Johan Storm]] devised [[Norvegia transcription|Norvegia]] for [[Norwegian language|Norwegian]] in 1884);{{Sfnp|Rischel|1989|p=45}} and Jespersen devised a system, named [[Dania transcription|Dania]], for the phonetic transcription of Danish (1890), which has remained in use for philological, dialectological and lexicographic work in Danish.{{sfnp|Basbøll|2021|p=538}} Jespersen was sceptical of a single phonetic transcription system for universal application, and did not use the IPA's [[International Phonetic Alphabet]].{{sfnp|Hjelmslev|1943|p=125}}

With continued encouragement by Thomsen and a new friendship with [[Paul Passy]], whom he met in Paris, Jespersen was  well informed on phonetics. His own major work on this was ''Fonetik'', published in 1897–1899. In it, Jespersen bases his descriptions on his observations of his own production of sounds in a variety of languages, where this production satisfies native speakers. Jespersen was keen to supplant metaphorical and impressionistic terms with those that described the vocal tract, and had considerable success. [[Jørgen Rischel]] calls ''Fonetik'' "a landmark in Danish phonetics because of its terminology", much of which has lasted.{{Sfnp|Rischel|1989|pp=45–46}} Stripped of content specific to Danish, but updated, it was published in German translation in 1904. 

The Danish-specific material within ''Fonetik'' was republished in 1906 within the booklet ''Modersmålets fonetik'' ("Phonetics of the mother tongue"). This treated not only the sounds of Danish but also its [[Prosody (linguistics)|prosody]], an area in which Jespersen was a pioneer. Repeatedly reprinted, the booklet was long used as a standard textbook.{{Sfnp|Rischel|1989|p=51}}

Two books, ''Phonetische Grundfragen'' ("Phonetics essentials") and ''Lehrbuch der Phonetik'' ("Textbook of phonetics"), presented portions of ''Fonetik'' to readers of German in 1904. Jespersen hoped for an English translation, and plans were made for a translation by [[Hans Jørgen Uldall]], and later for a revision by Uldall, no English translation ever appeared.{{Sfnp|Rischel|1989|p=56}} 

Rischel writes that: "It is Jespersen's amazing breadth in [his studies of phonetics], paired with his never failing linguistic intuition as a safeguard against errors or downright nonsense, which impresses the reader today."{{Sfnp|Rischel|1989|p=56}} In [[Eli Fischer-Jørgensen]]'s estimate (1979), Jespersen was not a great innovator, but was unusually adept at the pronunciation and description of articulatory phonetics, and also aware of the importance of contrast.{{sfnp|Basbøll|2021|pp=540–541}}

Early [[Dialectology|dialectological]] and other fieldwork on East Slesvig and [[Jutlandic|North Jutland]] dialects, [[Faroese language|Faroese]], and [[West Greenlandic]] work was indebted to Jespersen's methodology (although for the last, [[William Thalbitzer]], the researcher, "did not live up to Jespersen's standards at all").{{Sfnp|Rischel|1989|pp=52–53}}

Although not a phonologist himself, Jespersen was the first to propose a conceptual distinction between ''phonetics'' and ''phonology'' that is commonly observed today.{{Efn|"It would, perhaps, be advisable to restrict the word 'phonetics' to universal or general phonetics and to use the word ''phonology'' of the phenomena peculiar to a particular language (e.g. 'English Phonology').&nbsp;.&nbsp;.&nbsp;."<ref>{{Cite book | first=Otto | last=Jespersen | title=The philosophy of grammar | location=London | publisher=George Allen & Unwin | year=1924 | oclc=308037 | url=https://archive.org/details/dli.bengal.10689.9325/page/n5/mode/2up| via=Internet Archive | page=35}}</ref><ref>{{Cite book | title=Phonology in the twentieth century | edition=2nd | first=Stephen R. | last=Anderson | authorlink=Stephen R. Anderson | location=Berlin | publisher=Language Science Press | year=2021 | page=3 | isbn=978-3-96110-327-0 | doi=10.5281/zenodo.5509618 | url=https://langsci-press.org/catalog/book/327}} Also {{ISBN|978-3-98554-023-5}}.</ref> However, Jespersen's suggestion continues: "but this question of terminology is not very important".}}

''[[Stød]]'', "a particular kind of laryngealisation (creaky voice) characterizing some Danish syllables" had been studied since [[Jens Høysgaard]] in the mid-18th century, but Jespersen's synchronic study of ''stød'' and of its morphology and also his study of the relationship between the Danish ''stød'' and "the Norwegian and Swedish [[Pitch-accent language#Norwegian and Swedish|tonal ('musical') accents]]" were major advances from the work done by [[Rasmus Rask]], [[Karl Verner]], and [[Henry Sweet]].{{sfnp|Basbøll|2021|pp=545–546, 549–550}}

[[Hans Basbøll]] evaluates Jespersen as "a true pioneer in his analysis of stress" saying that:

<blockquote>he developed a whole system of types of stress and described it in detail: both syntactic principles of stress reduction (unitary stress, or unit accentuation), of compound stress, of value stress (different types of emphatic stress), and so on.{{sfnp|Basbøll|2021|p=548}}</blockquote>

Basbøll has coined the term "New Jespersen School" (''Ny-Jespersenianerne'') for "the main editors of [''Den Store Danske Udtaleordbog'' (a major pronunciation dictionary for Danish){{Efn|{{Cite book | last1=Brink | first1=Lars | first2=Jørn | last2=Lund | first3=Steffen | last3=Heger | first4=Jens Normann |last4=Jørgensen | year=1991 | title=Den store danske udtaleordbog | trans-title=The great Danish pronunciation dictionary | location=Copenhagen | publisher=Munksgaard | isbn=9788716066497 | language=da}}}}], namely, {{Ill|Lars Brink (linguist)|lt=Lars Brink|da|Lars Brink}}, [[Jørn Lund (linguist)|Jørn Lund]] and Steffen Heger, and their collaborators and pupils"; their major achievement aside from ''SDU'' has been Brink and Lund's two-volume historical phonetics work ''Dansk Rigsmål'' (1975).{{Sfnp|Rischel|1989|p=59}}{{Efn|{{Cite book | last1=Brink | first1=Lars | first2=Jørn | last2=Lund | year=1975 | title=Dansk rigsmål. Lydudviklingen siden 1840 med særligt henblik på sociolekterne i København | trans-title=Spoken standard Danish. The phonetic evolution since 1840 with particular reference to the sociolects in Copenhagen | location=Copenhagen | publisher=Gyldendal | isbn=9788701416818 | language=da}}}}{{sfnp|Basbøll|2021|p=554}}

===Concentration on English===
While still regarding himself as less of a scholar of English than a scholar of French, Jespersen published ''Kortfattet engelsk grammatik for tale- og skriftsproget'' ("A concise English grammar for the spoken and written language") in 1885. Most unusually for a grammar book, this employed phonetic script. Inge Kabell comments: "All other grammars of English published in Denmark were for many, many years to come modelled on it and all middle-aged Danes have been taught English according to the principles found in it."{{Sfnp|Kabell|2000|p=33}}

Jespersen continued to study in Paris (especially under [[Gaston Paris]]), England, Berlin (under [[Julius Zupitza]]), and Leipzig. Particularly important were his friendships with [[Paul Passy]] and [[Henry Sweet]]. Sweet's views on phonetics, grammar, and historical linguistics, and his concentration on English, had a great influence on Jespersen. Jespersen's choice of the [[Grammatical case|case]] system of English as the subject of his doctoral dissertation was probably also prompted by advice from [[Vilhelm Thomsen]] to prepare for a chair in English at the [[University of Copenhagen]] that would soon be vacant upon the retirement of [[George Stephens (philologist)|George Stephens]]. He successfully defended his dissertation in 1891. Once installed as chair, Jespersen devoted most of his energy to the study and teaching of English, but he retained his broader interests. His prolific output was of great importance for the linguistic study of all aspects of English, for linguistics in general, and to a lesser degree for Nordic philology. Jespersen was the first great linguist to hold the chair of English at the Copenhagen, while his friend {{Ill|Kristoffer Nyrop|ca||de||fr||it||ro||ru|Нюроп, Кристофер|sv}} had much the same role for the university's chair of French.{{sfnp|Hjelmslev|1943|p=122}}

Jespersen continued as chair of English until he retired in 1925, following his resolve not to continue after reaching 65, in order to help make way for younger scholars.{{sfnp|Hjelmslev|1943|p=123}}

===General syntax===
Jespersen advanced the concepts of ''rank'' in two papers: ''Sprogets logik'' (1913) and ''De to hovedarter af grammatiske forbindelser'' (1921); and in the latter, ''[[Nexus grammar|nexus]]'' as well.{{sfnp|Hjelmslev|1943|p=125}} In this theory of ranks Jespersen removes the parts of speech from the syntax, and differentiates between primaries, secondaries, and tertiaries; e.g. in ''well honed phrase'', the primary is ''phrase'', this being defined by a secondary, ''honed'', which itself is defined by a tertiary, ''well''. The term ''nexus'' is applied to sentences, structures similar to sentences and sentences in formation, in which two concepts are expressed in one unit; e.g., ''it rained, he ran indoors''. This term is qualified by a further concept called a ''junction'' which represents one idea, expressed by means of two or more elements, whereas a nexus combines two ideas. ''Junction'' and ''nexus'' have had a mixed evaluation: Hjelmslev finds the distinction between them confused, and Jespersen's theory of them in need of revision, in contrast to his refinement in "Tid og tempus" (1914){{Efn|1="[http://publ.royalacademy.dk/books/336/1939?lang=en Tid og tempus. Fortsatte logisk-grammatiske studier]". ''Oversigt over det Kongelige Danske Videnskabernes Selskabs Forhandlinger'' 1914, no.&nbsp;5–6, pp.&nbsp;367–420 – via the Royal Danish Academy of Arts and Letters.}} of Sweet's distinction between ''[[Grammatical tense|tense]]'' (Danish ''tempus'') and ''time'' (Danish ''tid'').{{sfnp|Hjelmslev|1943|pp=125–126}}

Jespersen's work helped point the way towards our current understanding of a grammatical ''[[Head (linguistics)|head]]''.<ref>{{Cite book | first=Evelien | last=Keizer | title=The English noun phrase: The nature of linguistic categorization | location=Cambridge | publisher=Cambridge University Press | year=2007 | isbn=978-0-521-84961-6 | page=53}}</ref>

In Hjelmslev's opinion, ''Negation in English and Other Languages'' (1917) offers a great number of observations and considerable food for thought, but fails to constitute a general examination of negation, for which purpose it would have to be based on more solid materials, from a greater variety of languages{{sfnp|Hjelmslev|1943|p=126}} (the overwhelming majority of the examples examined are from the [[Indo-European languages]] of west Europe). Jespersen coined the terms ''[[paratactic negation]]''{{Sfnp|Van der Wouden|1997|p=196}} and ''resumptive negation'' (negation with an element added to the end of the sentence to strengthen the already negative meaning of the sentence);{{Sfnp|Van der Wouden|1997|p=248}} he also advanced understanding of ''[[negative concord]]''.<ref>{{Cite book | first=Anastasia | last=Giannakidou | author-link=Anastasia Giannakidou | chapter=''N''-words and negative concord | volume=3 | page=328 | editor-first1=Martin | editor-last1=Everaert | editor-first2=Henk | editor-last2=van Riemsdijk | editor-link2=Henk van Riemsdijk | title=The Blackwell companion to syntax | location=Malden, Massachusetts | publisher=Blackwell | year=2006 |isbn=978-1-4051-1485-1}}</ref>

In ''The Philosophy of Grammar'' (1924) Jespersen challenges the accepted views of common concepts in [[grammar]] and proposes corrections to the basic definitions of [[grammatical case|case]], [[pronoun]], [[object (grammar)|object]], [[voice (grammar)|voice]] etc., and further develops his notions of ''Rank'' and ''Nexus''. In the 21st century this book is still used as one of the basic texts in modern [[structural linguistics]].{{Citation needed|date=May 2025}}

With ''The Philosophy of Grammar'' particularly in mind, [[Noam Chomsky]] said in 1975: "I think it is fair to say that the work of recent years tends generally to support the basic ideas that Jespersen outlined 50 years ago, and extends and advances the program that he outlined."<ref>{{Cite book | editor-first=Noam | editor-last=Chomsky | first=Noam | last=Chomsky | author-link=Noam Chomsky | chapter=Questions of form and interpretation | title=Essays on form and interpretation | location=New York | publisher=North-Holland | year=1977 | isbn=0-7204-8615-7 | orig-date=1975}} Also {{ISBN|0-444-00229-4}}.</ref>

===Evolution and progress of languages===
Jespersen wrote "That language ranks highest which goes farthest in the art of accomplishing much with little means, or, in other words, which is able to express the greatest amount of meaning with the simplest mechanism."<ref>{{Cite book | last=Jespersen | first=Otto | year=1894 | title=Progress in Language: With special reference to English | location=London | publisher=Sonnenschein | oclc=607098829 | url=https://archive.org/details/cu31924026448203 | via=Internet Archive | page=13}} {{Cite book | last=Jespersen | first=Otto | year=1922 | title=Language: Its Nature, Development and Origin | location=London | publisher=George Allen & Unwin | page=324}}</ref> Jespersen considered the efficiency of a language's phonology, lexicon and grammar,{{Sfnp|McElvenny|2017|p=419}} his view of grammar in reaction to [[August Wilhelm Schlegel]]'s contrasting estimates of "[[Synthetic language|synthetic]]" and "[[Analytic language|analytic]]" inflectional languages.{{Sfnp|McElvenny|2017|pp=419–420}} Schlegel, his brother [[Friedrich Schlegel]], and [[Wilhelm von Humboldt]] prized synthetic languages, and the ranking of languages that resulted became the generally received view.{{Sfnp|McElvenny|2017|p=420}} [[August Schleicher]] was a conspicuous proponent of the idea that several (such as Latin) among the older languages had attained a "synthetic" optimum, and languages that derived from these tended to degrade via the "analytic" towards an "[[Isolating language|isolating]]" extreme, the degree of degradation of a language increasing with "the richness and eventfulness of its speakers' history".{{Sfnp|McElvenny|2017|p=421}} 

Jespersen proposed the reverse, criticizing the needless complexities of "synthetic" grammar, and ascribing Schleicher's evaluations to "a grammar-school admiration, a Renaissance love of [Latin and Ancient Greek] and their literatures".<ref>''Progress in Language'', pp. 9–10; quoted in {{Sfnlink|McElvenny|2017|p=421}}.</ref>

Whereas Schleicher conceived language as a biological phenomenon, and thus subject to processes such as maturation, ageing and death, linguists of the mid 19th century such as [[Georg Curtius]], [[Johan Nikolai Madvig]] and [[William Dwight Whitney]] emphasized language as a human-developed tool for communication. By the end of the century this became the received conception of language.{{Sfnp|McElvenny|2017|p=422}} 

Jespersen thought of the uses of language as needing a balance between two factors: the ''ease'' of the speaker's expression of ideas, and the ''distinctness'' of that expression (and thus the ease of comprehension for the listener).<ref>''Efficiency in Linguistic Change'', pp. 391–392; quoted in {{Sfnlink|McElvenny|2017|p=422}}.</ref> The proximate sources of the pair were [[Georg von der Gabelentz]]'s ''Bequemlichkeitstrieb'' ('drive to comfort') and ''Deutlichkeitstrieb'' ('drive to distinctness', although ''Deutlichkeit'' had a broader meaning than did Jespersen's early formulations of ''distinctness'').{{Sfnp|McElvenny|2017|p=423}} Jespersen later recognized that distinctness should include playfulness, vividness and other factors, but they did not dislodge the ability to communicate from its foremost position.{{Sfnp|McElvenny|2017|p=424}}

Unlike Gabelentz, Jespersen was interested in extending the concepts of analyticity and efficiency to international auxiliary languages.{{Sfnp|McElvenny|2017|p=425}} Within negotiations among the [[Delegation for the Adoption of an International Auxiliary Language]] aimed at deciding which constructed language should receive the international backing of scholars, the greatest supporter of Jespersen's principles was the chemist [[Wilhelm Ostwald]], who had his own theory of ''Energetik'' ('energetics'), and for whom "Language was .&nbsp;.&nbsp;. a domain of culture calling out to be optimized through deliberate intervention".{{Sfnp|McElvenny|2017|p=427}} Thus for Jespersen, progress towards communicative efficiency is anyway inevitable,<ref>{{Cite book | first=Otto | last=Jespersen | date=1933 | chapter=Energetik der Sprache | title=Linguistica: Selected Papers in English, French and German | location=Copenhagen | publisher=Levin & Munskgaard | orig-date=1914 | pages=98–108 | oclc=459619574 | url=https://archive.org/details/dli.ministry.16424/page/n5/mode/2up | via=Internet Archive | language=de}}</ref> but can be assisted by language engineering.{{Sfnp|McElvenny|2017|p=428}}

From his doctoral dissertation of 1891 onwards, Jespersen maintained that over time language did not merely change but progressed. Originally inspired by [[Herbert Spencer|Spencer]]'s ideas on the progress of language, this was also a reaction against [[August Schleicher]]'s theory that, after increasing in complexity, languages become senescent and decay.{{sfnp|Hjelmslev|1943|p=127}} In his books ''Language: Its nature, development and origin'' (1922) and ''Efficiency in linguistic change'' (1941) and elsewhere, Jespersen attempted to show that an evolutionary perspective, in which the fittest expression (that whose efficiency is maximized with minimum effort) survived, explained language change over time.{{sfnp|Hjelmslev|1943|p=127}}

Hjelmslev criticizes the ambiguity of "efficiency" and "effort"; and adds that even if these are understood only loosely, there have been counter-examples.{{Efn|For these, Hjelmslev particularly credits [[Björn Collinder]]'s ''Introduktion i Språkvetenskapen'' ("Introduction to linguistics"; Stockholm 1941).}} He concludes that, as propounded by Jespersen, the thesis is far from convincing, but is put forward vividly and has aroused considerable interest.{{sfnp|Hjelmslev|1943|p=127}}

Jespersen's conception of evolution soon came to differ from Spencer's. Whereas Spencer believed that increased heterogeneity – synonymy, and the generation of new word classes, dialects and even languages – indicated progress, he found progress in simplicity and uniformity{{Sfnp|McElvenny|2017|p=429}} and:

<blockquote>Jespersen praised the "{{Thinspace}}'noiseless' machinery" of English,{{Efn|1={{Cite book | first=Otto | last=Jespersen | title=A Modern English Grammar on Historical Principles, Part VI: Morphology | location=Copenhagen | publisher=Ejnar Munksgaard | date=1942 | oclc=220412299 | page=85 | url=https://archive.org/details/modernenglishgra0000otto_u2o2/page/84/mode/2up | via=Internet Archive}} (McElvenny cites the 1954 edition; its pagination is the same.) Jespersen writes this in the context of "the formal identity of a great many words belonging to different word-classes" (largely thanks to [[Conversion (word formation)|conversion]]).}} the modern European language furthest down the analytic path, and the language most despised by Schleicher for precisely this analytic degeneracy.{{Sfnp|McElvenny|2017|p=429}}</blockquote>

In a review of ''Efficiency in Linguistic Change'', [[Bernard Bloch (linguist)|Bernard Bloch]] was particular clear in saying that while linguists, like anyone else, were entitled to their private opinions on the relative merits of languages, judging the utility or attractiveness of a language is not part of their job.{{Sfnp|McElvenny|2017|p=430}} But although Bloch was an American structuralist, following [[Leonard Bloomfield]], his reaction was much more extreme than that of Bloomfield, who thought that tackling questions such as relative efficiency were better postponed. 

A very different kind of opposition to Jespersen's conception came from [[Charles Bally]], whose [[stylistics]] concerns led him to concentrate on the affective dimension of language, for which processes such as polysemy and [[Clipping (morphology)|clipping]] are important, and thus to reject efficiency as an idea.{{Sfnp|McElvenny|2017|pp=433–434}} Bally's objections extended beyond this: for example, he claimed that the change from "synthetic" to "analytic" was at times reversed.{{Sfnp|McElvenny|2017|p=438}}

As for the beginnings of language:

<blockquote>[[Wilhelm von Humboldt|Humboldt]] held the view .&nbsp;.&nbsp;. that the origin of language lies in the natural urge to produce art.&nbsp;.&nbsp;.&nbsp;. [The idea, which] originated most probably with [[Giambattista Vico|Vico]] .&nbsp;.&nbsp;. lived on till the beginning of the 20th century. Jespersen .&nbsp;.&nbsp;. emphatically denies, against all evidence, the romanticist background of this theory, [yet] still defends the thesis that language originated in song, in love play and otherwise.&nbsp;.&nbsp;.&nbsp;. Nowadays [this view] is entirely forgotten.{{Efn|1=Seuren points to Jespersen's ''Progress in Language: With Special Reference to English'' (1894); and to his ''Language: Its Nature, Development and Origin'' (1922), pp.&nbsp;431–437.}}<ref>{{Cite book | first=Pieter A. M. | last=Seuren | author-link=Pieter Seuren | title=Western Linguistics: An Historical Introduction | location=Malden, Massachusetts | publisher=Blackwell | page=77 | isbn=978-0-631-20891-4}}</ref></blockquote>

Richard C. Smith considers ''Language: Its nature, development and origin'' to be Jespersen's "masterpiece".<ref name="warwick"/>

Jespersen advanced the study of the [[Great Vowel Shift]], and was the first to present it in diagram form; he also coined its name.{{Efn|1=More precisely, Jespersen writes "the great vowel-shift": with a hyphen, and not capitalized. {{Cite book | first=Otto | last=Jespersen | title=A Modern English grammar on historical principles. Part I: Sounds and spellings | location=London | publisher=George Allen & Unwin | url= | via= | year=1961 | orig-date=1909 | pages=231–47}}}}<ref>{{Cite journal | title=The rise and fall of the Great Vowel Shift? The changing ideological intersections of philology, historical linguistics, and literary history | first=Matthew | last=Giancarlo | journal=Representations | volume=76 | number=1 | date=Fall 2001 | jstor=10.1525/rep.2001.76.1.27 | page=38}}</ref>

===Child language===
As Jespersen believed that linguistics was a biological science and that in evolution [[Recapitulation theory|ontogeny recapitulates phylogeny]], his interest in historical linguistics led him both to examine child language and to propound [[interlinguistics]], the encouragement of linguistic progress.{{sfnp|Hjelmslev|1943|p=127}}

Jespersen's writings on child language appear in ''Nutidssprog hos børn og voxne'' (1916), ''Børnesprog'' (1923), ''Sproget: barnet, kvinden, slægten'' (1941); they are summarized within ''Language: Its nature, development, and origin'' (1922).{{sfnp|Hjelmslev|1943|p=127}}

===International auxiliary languages===
{{Ido sidebar |expanded=History}}
Jespersen applied both his theories on grammar and his ideas of efficiency of expression into the quest for an [[international auxiliary language]]. He was an early supporter of the [[Esperanto]] offshoot [[Ido]], collaborating with [[Louis Couturat]] and others on ''International Language and Science'' (1910), a book advocating its adoption.{{Efn|Jespersen, "Linguistic principles necessary for the construction of an international auxiliary language, with an appendix on the criticism of Esperanto"; chapter 3 (pp.&nbsp;27–41) of L[ouis] Couturat, O[tto] Jespersen, [[Richard Lorenz (chemist)|R[ichard] Lorenz]], [[Wilhelm Ostwald|W[ilhelm] Ostwald]], and [[Leopold Pfaundler|L[eopold] Pfaundler]], ''[https://archive.org/details/internationallan00pfaurich International Language and Science: Considerations on the Introduction of an International Language into Science]''. London: Constable, 1910.}}{{sfnp|Hjelmslev|1943|p=127}}

Jespersen later broke with Ido and created an alternative, [[Novial]]. His significant publications here include ''An International language'' (1928), ''Novial Lexike'' (1930), and "A new science: Interlinguistics" (1931).{{Efn|Jespersen, "A new science: Interlinguistics", ''Psyche'', vol. 11 (1931), pp.&nbsp;57–67.}}{{sfnp|Hjelmslev|1943|p=127}}

He also worked with the [[International Auxiliary Language Association]].<ref>{{Cite journal | last=Falk | first=Julia S. | author-link=Julia S. Falk | title=Words without grammar: Linguists and the international language movement in the United States | journal=Language and Communication | volume=15 | number=3 | pages=241–259 | year=1995 | doi=10.1016/0271-5309(95)00010-N}}</ref>

===The English language===
The seven-volume, descriptive reference work ''[[A Modern English Grammar on Historical Principles]]'' (1909–1949) is likely Jespersen's most influential work and concentrates on syntax,

Jespersen's specialism for the longest period was the English language. Within this, the foremost work was ''[[A Modern English Grammar on Historical Principles]]'', published in six volumes during his lifetime, from 1909 to 1942, and a seventh, posthumous volume in 1949. The first volume is devoted to historical phonetics, the sixth to morphology (both derivational and inflectional) Five of the seven volumes are devoted to syntax, which Jespersen particularly enjoyed.{{Efn|1="When I took up work again after a rest necessitated by over-strain during a nine months' stay in America, I wanted something pleasurable to do and thought Syntax more attractive than Morphology.&nbsp;.&nbsp;.&nbsp;." {{Cite book| first=Otto | last=Jespersen | location=London | publisher=George Allen & Unwin | title=A Modern English grammar on historical principles. Part II: Syntax (first volume) | orig-date=1914 | year=1954 | page=v | url=https://archive.org/details/jespersen-1954-a-modern-english-grammar-on-historical-principles-part-ii-syntax-first-volume | via=Internet Archive}}}}

''A Modern English grammar'' had a high repute at the time: writing in Jespersen's obituary, Helmslev calls it a "monumental work", one that "will maintain its immense value for an incalculable future thanks to the rich documentation of facts it provides".{{Efn|1="[Un] œuvre monumentale.&nbsp;.&nbsp;.&nbsp;. Ce grand ouvrage .&nbsp;.&nbsp;. conservera pour un avenir incalculable une très haute valeur par la riche documentation de faits qu'il apporte."}}{{sfnp|Hjelmslev|1943|p=128}}

In his own work ''[[The Syntactic Phenomena of English]]'' (1988), [[James D. McCawley]] attributes various of his analyses, or the insights pointing towards them, to Jespersen: [[Raising (syntax)|raising]];{{Sfnp|McCawley|1988|loc=vol.&nbsp;1, pp.&nbsp;122,&nbsp;149}} "worthwhile criticism of traditional systems of [[part of speech|parts of speech]]"{{Sfnp|McCawley|1988|loc=vol.&nbsp;1, p.&nbsp;204}} and classification of what are traditionally termed "[[subordinating conjunction]]s" (as in "You must look at this ''<u>before</u> you leave''") as [[preposition]]s with sentential [[Object (grammar)|objects]];{{Sfnp|McCawley|1988|loc=vol.&nbsp;1, p.&nbsp;191}} and more specifically, classification of ''that'' in [[relative clause]]s (as in "The necktie ''<u>that</u> he bought'' was polyester") not as a [[relative pronoun]] but as a [[complementizer]].{{Sfnp|McCawley|1988|loc=vol.&nbsp;2, p.&nbsp;461}} Asked how the 20th-century Dutch grammarians of English [[Hendrik Poutsma]], [[Etsko Kruisinga]] and [[R. W. Zandvoort|R.&nbsp;W. Zandvoort]] compared with Jespersen, McCawley replied: "Of course, Jespersen is in a class by himself. He was a fantastically original, broad, and deep thinker."<ref>{{Cite journal | title=An interview with professor James D. McCawley | first=F.G.A.M. |last=Aarts | journal=Forum der Letteren | year=1977 | url=https://www.dbnl.org/tekst/_for004197701_01/_for004197701_01_0020.php | via=DBNL | page=232}}</ref>

''Growth and Structure of the English Language'' (1905, and reprinted at numerous times thereafter) is a broad history of the English language. It won Jespersen the [[Prix Volney]].{{sfnp|Hjelmslev|1943|p=129}} In 1989, [[Hans Frede Nielsen]] wrote that:

<blockquote>[It] can be read as the homage paid by an Anglophile to the English language which is praised for its business-like, virile qualities, its conciseness, logic and sobriety — to say nothing of its noble, rich, pliant and expressive character.&nbsp;.&nbsp;.&nbsp;. No wonder that [the book] became so popular in the English-speaking world and among Anglophiles elsewhere.<ref>{{Harvtxt|Nielsen|1989a|pp=70–71}} Within this, Nielsen cites in particular ''Growth and Structure of the English Language'' (9th edition, 1938), pp.&nbsp;2–16, 234.</ref></blockquote>

He described it as "probably the most widely read introduction to the history of the English language ever written".{{Sfnp|Nielsen|1989a|p=61}}

''Essentials of English Grammar'' (1933), primarily intended for university teaching, is for the most part synchronic.{{sfnp|Hjelmslev|1943|pp=129–130}} [[W. Nelson Francis]] described it as "arguably [Jespersen's] most familiar and popular book".{{Sfnp|Francis|1989|p=97}}

Terms related to English that were introduced by Jespersen and are still widely used today include ''[[cleft sentence]]'',<ref>{{Cite book | first=Peter C. | last=Collins | title=Cleft and pseudo-cleft constructions in English | location=London | publisher=Routledge | year=1991 | isbn=0-415-06328-0 | page=3}}</ref><ref>{{Cite book | first=Marcel | last=den Dikken | chapter=Specificational copular sentences and pseudoclefts | volume=4 | page=306 | editor-first1=Martin | editor-last1=Everaert | editor-first2=Henk | editor-last2=van Riemsdijk | editor-link2=Henk van Riemsdijk | title=The Blackwell companion to syntax | location=Malden, Massachusetts | publisher=Blackwell | year=2006 |isbn=978-1-4051-1485-1 }}</ref> ''[[content clause]]'',{{Sfnp|Aarts|Chalker|Weiner|2014|p=96}} ''[[light verb]]'',<ref>{{Cite book | first=Tara | last=Mohanan | author-link=Tara Mohanan | chapter=Grammatical verbs (with special reference to light verbs) | volume=2 | pages=461–462 | editor-first1=Martin | editor-last1=Everaert | editor-first2=Henk | editor-last2=van Riemsdijk | editor-link2=Henk van Riemsdijk | title=The Blackwell companion to syntax | location=Malden, Massachusetts | publisher=Blackwell | year=2006 |isbn=978-1-4051-1485-1}}</ref> ''[[mass noun]]'',{{Sfnp|Aarts|Chalker|Weiner|2014|pp=244–245}} and ''[[Yes–no question|yes-or-no question]]''.{{Sfnp|Aarts|Chalker|Weiner|2014|p=222}} Jespersen's writings have also influenced today's conceptions of ''[[existential sentence]]''.<ref>{{Cite book | first=Andrea | last=Moro | author-link=Andrea Moro | chapter=Expletive sentences and expletive ''there'' | volume=2 | pages=210–211 | editor-first1=Martin | editor-last1=Everaert | editor-first2=Henk | editor-last2=van Riemsdijk | editor-link2=Henk van Riemsdijk | title=The Blackwell companion to syntax | location=Malden, Massachusetts | publisher=Blackwell | year=2006 |isbn=978-1-4051-1485-1}}</ref>

Robert I. Binnick calls Jespersen "one of the greatest students of the English language .&nbsp;.&nbsp;.&nbsp;, at once the last of the traditional grammarians and the first modern linguist–grammarian".<ref>{{Cite book | first=Robert I. | last=Binnick | title=Time and the verb: A guide to tense and aspect |location=New York | publisher=Oxford University Press | year=1991 | isbn=0-19-506206-X | pages=53–54}}</ref>

===Other fields===
''Mankind, Nation and Individual: From a linguistic point of view'' (1925) is one of the pioneering works on [[sociolinguistics]].

Late in his life Jespersen published ''Analytic Syntax'' (1937), in which he presents his views on syntactic structure using an idiosyncratic shorthand notation.

===Influences and allegiances===
During the decades of his activity, Jespersen followed what other, younger linguists were doing but refrained from unreservedly welcoming any advance, let alone from aligning himself with any new approach. He remained individualistic, but "there was a conservative streak in his radicalism"{{efn|1="[I]l y avait dans son radicalisme un trait conservateur"}} as he seemed to take seriously only the standpoints that had influenced him in his youth and to interpret newer work as mere repetition of this or that older theory.{{sfnp|Hjelmslev|1943|p=129}}

Jespersen's main interest was not that of seeking patterns and explanations of the [[Langue and parole|''langue'' behind ''parole'']], but rather its opposite, the major concern of the phonetics and semantics of his youth: "the psychophysiological fact of ''parole''".{{efn|1="[La grande réalité] du fait psychophysiologique de la parole"}}{{sfnp|Hjelmslev|1943|p=129}}