The term 'multi-competence' was originally defined as 'the compound state of a mind with two grammars' (Cook, 1991); in the context of that paper, ‘grammar’ was used in the Chomskyan sense of the total knowledge of language in the mind (the I-language) leading some people to infer wrongly that multi-competence was restricted to syntax. So multi-competence is now usually said to be ‘the knowledge of more than one language in the same mind’ (Cook, 1994). Multi-competence thus presents a view of second language acquisition (SLA) based on the second language (L2) user as a whole person rather than on the monolingual native speaker. It is neither particularly a psychological concept, as some have claimed (Kelly Hall et al, 2006), nor particularly sociological: It is a perspective for viewing both approaches to SLA and thus applies both to the individual and to the community. It is perhaps closest to approaches that treat language as a continuously changing system (De Bot et al, 2005; Herdina & Jessner, 2002). Accounts of the historical development of the concept can be found in Cook (2006; 2007a); a bibliography is available (Murahata & Murahata, 2008).

Multi-competence therefore involves the whole mind of the speaker, not simply their first language (L1) or their second. It assumes that someone who knows two or more languages is a different person from a monolingual and so needs to be looked at in their own right rather than as a deficient monolingual, an idea put forward by Grosjean (1989) from a different background. Multi-competence is thus not a model nor a theory so much as an overall perspective or framework: It changes the angle from which second language acquisition is viewed. It constitutes a bilingual ‘wholistic’ interpretation of bilingualism as opposed to a monolingual ‘fractional’ interpretation of bilingualism, in Grosjean ( 2009)’s terms.

In the 1960s the conceptual breakthrough in the linguistic study of language acquisition was the independent grammars assumption that children do not distort the adult language system but invent systems of their own, put forward by McNeill (1966) and Braine (1963) among others. This insisted that children are not defective speakers of adult language but speakers of a distinct language with its own rules, vocabulary and phonology, which gradually develop into the adult’s linguistic competence. The idea soon crossed over into the nascent field of second language acquisition (SLA) research through such concepts as 'approximative system' (Nemser, 1971) and ‘interlanguage’ (Selinker, 1972). It was generally assumed that L2 learners too speak languages that do not correspond to established languages such as Spanish or English but have their own properties, created by L2 learners in a similar way to L1 children. Interlanguage opened the floodgates of SLA research and became an almost unchallenged axiom.

Multi-competence and the native speaker

Multi-competence proposed to take the concept of interlanguage seriously. If L2 users are to be treated in their own right, the native speaker has no particular status: It is the users’ own language that matters. This remains the key aspect of multi-competence. If a native speaker is someone who still speaks the first language (L1) that they learnt in childhood, being a native speaker is “an unalterable historic fact; you cannot change your native language any more than you can change who brought you up” (Cook, 1999); you can try to pass as a native speaker of another language but never become one – by definition. Multi-competence thus includes the first language, the interlanguage and other aspects of the L2 user’s mind.

Some arguments in favour of multi-competence are:

-          the normality of the L2 user. In many parts of the world like India and the Cameroon, monolinguals form a small minority: Everybody has to use more than one language in their everyday lives. Brutt-Griffler (2002) has argued for the multi-competence of the community: Rather than a community being defined by a single language, many communities in say India or Central Africa have multiple languages at their core, specialized by function and so on. While it is hard to get exact figures, multi-competence is probably not so much an exception as the norm for twenty-first century human beings.

-          the rights of individuals. Linguistics has progressively refused to classify speakers in terms of groups of which they are not, and never could be, members, first granting independence to primitive languages (Boas, 1920/1940), then freeing children’s language from adults’ (the independent grammars assumption), then liberating black English speakers from white (Labov, 1969), working-class restricted code from middle-class elaborated code (Bernstein, 1971) and women’s language from men’s. The only group still to be judged by the standards of another is L2 users. But they too have the right to use language appropriately for their needs, not for those of a native speaker group to which they can never belong.

Despite its acceptance of interlanguage, much SLA research has continued to measure L2 users against native speakers. Inevitably what L2 users do is seen as a mistake whenever it fails to conform to the language of monolingual native speakers and the L2 users’ level of language proficiency is seen as deficient rather than different: It’s all right if your English accent proclaims you come from Newcastle upon Tyne but not from Paris. This native speaker comparison lurks behind such typical statements as: “Unfortunately, language mastery is not often the outcome of SLA” (Larsen Freeman & Long, 1991, p. 153); or “The lack of general guaranteed success is the most striking characteristic of adult foreign language learning” (Bley-Vroman, 1989, p. 42). It is possible to measure ducks in terms of swans. But when everything has to satisfy the swan criteria, the unique qualities of ducks will always elude the observer, just as black English, working-class English and women’s language were once seen as pale shadows of a ‘true’ variety. Uniquely bilingual functions of language like codeswitching and translation will never show up in a native speaker model; unique grammatical forms of L2 users like the rules of the Basic Variety (Klein & Perdue, 1997) will appear just as mistakes.

While overt denigration of L2 users for not being native speakers is now less common, the perennial SLA research questions continue to revolve around whether the L2 user is like a native speaker: Whether age affects L2 learning depends on speaking like a native – “[we] have yet to show that later learners can achieve the same level of phonology as native speakers in production” (DeKeyser & Larson Hall, 2005, p. 96); the ultimate attainment of L2 learners is assessed in terms of “absolute native-like command of an L2” (Hyltenstam & Abrahamsson, 2003); whether L2 learners have access to Universal Grammar is seen as depending on whether they attain the identical grammar to native speakers (Clahsen & Muysken, 1987). The typical SLA research techniques outlined in Cook (1997) consist of Error Analysis (i.e. mostly defining errors as things native speakers would not do), obligatory occurrence (Pienemann, 1998) (omitting elements that native speakers would not leave out), grammaticality judgements (based on the ‘correct’ native speaker grammar), elicited imitation (Cook, 1973) (defined by how the native speaker would repeat), and so on. The commitment to the independent L2 user is often a matter of rhetoric rather than the reality reflected in the research questions and techniques of SLA research.

But what term should be used to describe people who are multicompetent? People who acquire their first language are not regarded as L1 learners for the rest of their lives. Why should people who know more than one language be treated differently? Calling people L2 learners seemed to confirm their subordinate status. Hence the more neutral term ‘L2 user’ was introduced. ‘L2 user’ refers to people who know and use a second lang­uage at any level; multi-competence is not restricted to high-level balanced bilinguals but concerns the mind of any user of a second language at any level of achievement. ‘L2 learner’ is reserved for people who have no everyday use of the second language, say children in foreign language classrooms. Of course L2 users may also be L2 learners at different times of life or indeed times of day – an L2 learner of English in London who steps out of the classroom immediately become an L2 user of English. More recently at least five different groups of L2 users have been distinguished (Cook, 2009a): Those using an L2 within a larger community, say Arabic residents of Berlin using German; those using it internationally for restricted functions, for example Muslims using Arabic for religious purposes regardless of their first language and the country in which they live whether Germany or Saudi Arabia; those using it globally for a wide range of functions, primarily nowadays the use of English as a Lingua Franca (ELF) say for business, tourism or electronic communication; those using it with spouses, siblings or friends with different first languages (Piller, 2002); and those historically from a particular community (re-) acquiring its language for cultural use, say British Chinese speakers of Cantonese learning Mandarin. Each of these groups undoubtedly have specific qualities that do not generalize to L2 learning in general. The people usually studied in SLA research are classroom L2 learners, many of whom are not and never will be L2 users, for example Chinese children learning English at school in Shanghai, and immigrants adjusting to a new country (hence the importance of Age of Arrival in much SLA research).

The multi-competence perspective was first supported by reinterpreting research from various domains to show the effects of learning second languages on the human mind (Cook, 1992). But it led to research specifically aimed at multi-competence that generated research questions which had previously barely been mentioned.

Effects of the L2 on the L1

A vast amount of SLA research has looked at the effects of the first language on the second, labelled ‘transfer’ or ‘crosslinguistic influence’, still a favorite topic for dissertations exploring yet more first languages or novel aspects of language. By looking at the whole learner’s mind, multi-competence opened up reverse transfer from the second language to the first and other forms of transfer (Jarvis & Pavlenko, 2009). A new research question was then: Do you still speak your first language like a monolingual native speaker when you know another language? A negative answer to this could reverberate across SLA research, and indeed much linguistics, as it would be unsafe to regard any person who knows another language as having ‘normal’ monolingual linguistic competence; “the judgments about English of Bloomfield, Halliday or Chomsky are not trustworthy, except where they are supported by evidence from ‘pure’ monolinguals” (Cook, 2002): the founder of linguistic relativity, Whorf (1941/1956), based his ideas about the indigenous American language Hopi in large part on an informant living in New York and so an L2 user.

In virtually every aspect of language studied, L2 users have turned out to be different from monolinguals. To take some representative studies:

-          phonology. Much research has shown the changes in Voice Onset Time (the duration of silence that distinguishes voiced and unvoiced plosive consonants) in the L2 user’s first language, for example English/Spanish (Zampini & Green, 2001). L1 intonation is also influenced by the L2, for example in Dutch users of Greek (Mennen, 2004).

-          lexicons. Since Caramazza & Brones (1980), many have argued for a single lexicon in the L2 user’s mind where words from one language are stored alongside words from the other. An L2 user seems unable to switch off one language entirely while processing another, only to lower the level of activation. Spivey & Marian (1999) for example showed in an eye-tracking task that words from one language were activated even when processing the other.

-          syntax. The L1 syntax of the L2 user is subtly altered by the second language they know. Using a Competition Model paradigm, Cook et al (2003) found that the cues to the processing of L1 word order change when another language is known. Balcom (2003) found that French L2 users of English had different grammaticality judgements of French ‘middle’ constructions from monolinguals.

-          pragmatics. Russians who knew English interpret film sequences differently from monolinguals (Pavlenko, 2003). L2 users indeed have a range of functions for language such as codeswitching and translation unknown to monolinguals.

Rather than enumerate further examples, the reader is referred to Cook (2003), which was devoted to this issue.

More than language has changed in the L2 user’s mind. Learning another language helps with learning to read the first language (Yelland et al, 1993), with metalinguistic awareness (Bialystok, 2001), and with the ability to write essays in the first language (Kecskes & Papp, 2000). Knowing another language delays the onset of Alzheimer’s disease (Bialystok, Craik, Klein & Viswanathan, 2004), leads to greater density of connections in the corpus callosum area that connects left and right hemispheres of the brain (Coggins et al, 2004), and develops the areas of the brain responsible for control (Green, 2010.). All of these support the proposition that the L2 user is a distinct kind of person from a monolingual.

Bilingual Cognition

The focus in recent research has been on the different ways in which L2 users think, surveyed in Cook & Bassetti (2010). The research looks at well-known areas where cognitive difference have been shown to occur crosslinguistically between a pair of languages and then sees how L2 users of the two languages think. Typical areas include:

-          shape and material. Imai and Gentner (1997) showed that Japanese classify objects more by material, English speakers by shape. Cook et al (2006) found that Japanese L2 users of English living in England had moved some way towards the English preference.

-          colors. Many languages recognize two distinct ‘blue’ colors where English has only one. Athanasopoulos (2009) showed that speakers of Greek who had learnt English had altered classifications of colors.

-          gender. Speakers of grammatical ‘arbitrary’ gender languages tend to assign gender to inanimate objects in the natural world; this effect is diminished for those who know two languages with different gender systems (Bassetti, 2007).

-          motion. Descriptions of motion events in L2 learners are affected by their first language (Jarvis & Odlin, 2000). In particular Talmy’s (1985) division between satellite and verb-framed languages has generated masses of L2 research, showing effects of bilingualism on ideas of motion, for example Hohenstein, Eisenberg & Naigles (2006).

Multi-competence and language teaching

The multi-competence idea has important implications for language teaching, which has often seen its task as making students as like native speakers as possible. Multi-competence is now starting to be utilized in books on SLA and language teaching such as Cook (2008), Ortega (2009) and Scott (2009).

-          Goals of language teaching. Multi-competence takes the goal of language teaching as producing a successful L2 user, not an imitation native speaker. It thus aligns with the English as Lingua Franca (ELF) movement (Seidlhofer, 2004) rather than with the Common European Framework of Reference (Council of Europe, 2001), which seems to use the native rather than the L2 user as a touchstone.

-          The language teaching classroom. The multi-competence perspective does not see any virtue in making the students use only the second language in the classroom since this denies the very existence of the first language in their minds. It advocates principled use of the second language when classroom goals can be achieved more efficiently by its use (Cook, 1999).

-          Native speaker language teachers. A non-native speaker teacher (NNST) is an L2 user who has acquired another language; a native speaker teacher (NST) is not. Hence the NNST can present a role model for the students, has learnt the language by a similar route to the students and can codeswitch to the students’ own language when necessary. The NST’s only substantive advantage may be a greater facility in the target language, but as a native speaker not as an L2 user. Recent attitudes are conveyed in Llurda (2005).

Overall the development of a multi-competence perspective has been fruitful in suggesting not only new interpretations of existing theories and phenomena but also new research questions to be tackled. It has gone some way to redressing the bias in favor of the native speaker. But its importance extends beyond SLA research to linguistics, psycholinguistics and psychology in its insistence on the uniqueness of the L2 user. The fundamental questions of linguistic competence and language acquisition are different if most human minds in fact know more than language. In particular it is a “question whether UG theory can achieve its basic task of describing how human minds acquire, store and use language without taking into account the minds that cope with more than one language” (Cook, 2009b). Chomsky’s four questions for linguistics (Chomsky, 1988), namely accounting for knowledge of language, its acquisition, use and physical manifestation in the brain, are transformed when multi-competence – knowledge of languages in the plural – is the normal state of the human mind, is the norm: rather than the dominant form of language knowledge, monolingualism becomes an aberration due to linguistic deprivation of second language input. ‘The monolingual native speaker is language-deprived; they would have acquired multi-competence in more than one language if their caretakers had not deprived them of a second language’ (Cook, 2010).

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