linguistics Linguistics is the science, scientific study of human language. It is called a scientific study because it entails a comprehensive, systematic, objective, and precise analysis of all aspects of language, particularly its nature and structure ...

, the unidirectionality hypothesis proposes that grammaticalisation works in a single direction. That is,

pronoun In linguistics and grammar, a pronoun (abbreviated ) is a word or a group of words that one may substitute for a noun or noun phrase. Pronouns have traditionally been regarded as one of the parts of speech, but some modern theorists would not c ...

s may fuse with verbs, or prepositions may fuse with nouns, to create new

inflection In linguistic morphology, inflection (or inflexion) is a process of word formation in which a word is modified to express different grammatical categories such as tense, case, voice, aspect, person, number, gender, mood, animacy, and ...

al systems, but inflectional endings do not break off to create new pronouns or prepositions. The unidirectionality hypothesis does not claim that linguistic change ''will'' occur in any particular instance, only that if it ''does'' occur, it will be in the direction of

lexical word In grammar, a part of speech or part-of-speech ( abbreviated as POS or PoS, also known as word class or grammatical category) is a category of words (or, more generally, of lexical items) that have similar grammatical properties. Words that are ass ...

to grammatical word and not the other way around. Certain schools of linguistics object to the unidirectionality hypothesis on theoretical grounds, believing that there should be no favoured direction in the evolution of grammatical forms, and have proposed numerous counter-examples. However, most of these proposals show a lack of understanding of the hypothesis or of the history of the languages in question, and are instead examples of lexicalisation. True counter-examples to unidirectionality appear to be rare and require unusual conditions.

A counter-example

One counter-example is the evolution of a new pronoun for "we" out of verbal conjugations in northern dialects of Irish Gaelic. It's as if

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many Latin American countries **Spanish cuisine Other places * Spanish, Ontario, Can ...

''hablamos'' (we speak) were reanalyzed as ''habla mos,'' with ''mos'' becoming a new pronoun "we" that replaced the existing pronoun ''nosotros''. In Irish this required a rather special set of circumstances. Unusually for a European language, Irish is verb-initial, as can be seen in phrases such as :''Chonaic mé thú'' "I saw you" (literally ''saw I thee''). In

Old Irish Old Irish, also called Old Gaelic ( sga, Goídelc, Ogham script: ᚌᚑᚔᚇᚓᚂᚉ; ga, Sean-Ghaeilge; gd, Seann-Ghàidhlig; gv, Shenn Yernish or ), is the oldest form of the Goidelic/Gaelic language for which there are extensive writt ...

the verb was inflected for person, as it still is in the south of Ireland. The verb 'to be' was inflected as follows: With such a system, there was no need for pronouns except for emphasis, as is the case with

today. However, in the north of Ireland, the system eroded, and most of the inflectional endings disappeared. The use of the subject pronouns then became obligatory to disambiguate the person of the verb. A similar change has taken place in French, where the loss of most of the verbal endings (in the spoken language at least) has meant that subject pronouns are now required. The subject pronouns of modern Irish are the following: These were added to the verb wherever the inflections had disappeared. Since the subject comes after the verb in Irish, the pronouns effectively replaced the old verbal endings: {, class=wikitable !''to be''
(modern)!!singular!!plural , - , 1, , táim ''or''
tá mé, , táimid , - , 2, , tá tú, , tá sibh , - , 3, , tá sé,
tá sí, , tá siad The first-person singular ("I") form is still retained in some areas but appears to be in the process of dropping out and being replaced by the pronoun ''mé''. However, the first-person plural ("we") form—the only ending that was a complete syllable—is robust everywhere, and the pronoun ''sinn'' is not used in this situation. This happened not just with the verb 'to be' but with all Irish verbs. The unidirectionality hypothesis would predict that this paradigm would either remain as it is, with the pronouns retaining their status as independent words, or else that they might fuse with the verb into a new verbal conjugational system, as existed in Old Irish. However, something more unusual occurred: the pronouns did retain their separate status, but the first-person plural verbal ending ''-mid'' was reanalyzed as a pronoun, by analogy with the other persons. Thus Irish has acquired a new pronoun for "we", ''muid'', which can be used as an independent word, for example as an emphatic ''muide'' "us": If someone asks "Who is there?", an Irish speaker might reply, ''Is muide'' ("It is us"). This new pronoun appears to be replacing the original pronoun ''sinn''.

References

*''The Evolution of Grammar: Tense, aspect, and modality in the languages of the world.'' Joan Bybee, Revere Perkins, & William Pagliuca. University of Chicago Press, 1994.

External links

On the Terrible De-Grammaticalization in Hujulukinat
: A humorous exploration of radical, rapid violations of the unidirectionality hypothesis. Historical linguistics