**2. Background of study**

Numerous scientifically supported research activities inspired by the UNESCO [13] and UNESCO [14] policy orientation on the promotion of linguistic and cultural diversity have employed different perspectives and definitions for the concept of bilingualism and multilingualism. The term multilingualism as employed here cuts across those implied or asseverated in these reports. Thus, multilingualism is considered first, as implying bilingualism, since in order to be a multilingual, one has to be exposed to at least one situation or experience of bilingualism. It is anticipated that all the features that hold for multilingualism do so too for bilingualism. But since multilingualism involves the use of more than two languages, it manifests a more complex scenario with operational characteristics that obviously overlap with those of the bilingual setting.

Nonetheless, the definition of multilingualism is as varied as the different interrelated disciplines that identify with it and the objective(s) of the research in question. The European Commission [15], for example, defines multilingualism as "the ability of societies, institutions, groups and individuals to engage, on a regular basis, with more than one language in their day-to-day lives." This definition conscripts both multilingualism and bilingualism in the expression "… more than one language…," thus considering them as phenomena with similar semantic content, properties, and consequences. It is this same assumption that is projected by Li [16], who looks at multilingualism in the light of "anyone who can communicate in more than one language, be it active (through speaking and writing) or passive (through listening and reading)." Li aligns with the school of thought for whom a multilingual person, group, or setting engenders *basic* proficiency in the use, speaking, or understanding of more than one language. It is the same perception that is clearly underscored by scholars like Skutnabb-Kangas and McCarty, [17] with claims that "today, the idea of perfect mastery and perfect balance of two or more languages is no longer considered a requirement for being bilingual or multilingual." Concern thus shifts to the number of languages rather than the proficiency in their usage, an idea likewise maintained by authors like Vildomec [18], McArthur [19], and Edwards [20]. These consider multilingualism as "the ability to use three or more languages either separately or in various degrees of code-mixing. Different languages are used for different purposes, competence in each varying according to such factors as register, occupation, and education." It is thus variously implied that the degree of proficiency is not essential; basic speaking and listening skills (communicative skills) of the speaker(s) are all it takes to be considered as bilingual or multilingual.

more advantageous than monolingualism; it rather appraises a range of multidimensional evidences that have been established from varied research findings, highlighting the benefits of bilingualism in individuals or plurilingualism and multilingualism in different societies. It explores the phenomenon of bilingualism and multilingualism, how it can be a "blessing" and not a "curse" at both levels of its manifestation. The chapter is thus largely a compendium of empirical evidence of the advantages of individual and societal bilingualism/multilingualism and linguistic diversity of nations as established by research findings in the last several decades from studies by linguists and scholars such as Byram [5], Baker et al. [6], Bialystok et al. [7], Ewert [12], Paradowski et al. [9], Grin et al. [10], etc. Thus, our focus is not only on identifying the different advantages (a thing already partially covered in many reports) but also in bringing out the different research techniques and methodologies that have been used in arriving at the different claims or justifications of advantages for these bilinguals or multilinguals. Our discussion is presented in two major sections. The first on the "advantages of individual bilingualism/multilingualism" outlines such themes as cognitive development advantages of bilingualism; the brain of bilinguals as a neurophysiological organ; advantages for Alzheimer bilinguals; linguistic awareness, benefits of communicative ability, and competence; advantages in academic or educational performance; sociocultural, economic, and political advantages; etc. The second section handles benefits of "societal multilingualism," i.e., the advantages of multilingualism for communities and the nation. The two divides individual and societal bilingualism/multilingualism—are linked by our discussion of how they can be a blessing to any democratic nation, ending in concluding remarks that cap the

Numerous scientifically supported research activities inspired by the UNESCO [13] and UNESCO [14] policy orientation on the promotion of linguistic and cultural diversity have employed different perspectives and definitions for the concept of bilingualism and multilingualism. The term multilingualism as employed here cuts across those implied or asseverated in these reports. Thus, multilingualism is considered first, as implying bilingualism, since in order to be a multilingual, one has to be exposed to at least one situation or experience of bilingualism. It is anticipated that all the features that hold for multilingualism do so too for bilingualism. But since multilingualism involves the use of more than two languages, it manifests a more complex scenario with operational characteristics that obviously overlap with

Nonetheless, the definition of multilingualism is as varied as the different interrelated disciplines that identify with it and the objective(s) of the research in question. The European Commission [15], for example, defines multilingualism as "the ability of societies, institutions, groups and individuals to engage, on a regular basis, with more than one language in their day-to-day lives." This definition conscripts both multilingualism and bilingualism in the expression "… more than one language…," thus considering them as phenomena

research findings.

16 Multilingualism and Bilingualism

**2. Background of study**

those of the bilingual setting.

Despite different perceptions, the different definition perspectives converge on the assumption that the multilingual setting needs to have a speaker, group, nation, or activity/environment, where *two or more languages* are used for communication. None highlights considerations of the situational use/domain, function, degree of fluency, different manner, time, or place of acquisition of the second language and other languages.

All taken into consideration, the perspective adopted in this study is that of Aronin and O Laoire [21] that "plurilingualism" limits its scope to only individuals and not societal multilingualism. By implication, discussions about the different types of multilingualism, such as coordinate bilingualism, referring to person's learning of two languages in separate environments/contexts; subcoordinate bilingualism, referring to the acquisition of the second language (L2) with the help of the first language (L1); compound bilingualism, which is the learning of two languages in the same environment, time, and even context; and the different stages of acquisitions and their degrees of proficiency levels as detailed by Bassetti and Cook [22] and Baker [23], are beyond the scope of this study. They, however, constitute useful typologies of the phenomenon for those interested in conceptual details.

There are, no doubt, some drawbacks involved in the active usage of more than two languages, including negative language contact phenomena like interferences, negative transfer or overgeneralization of language rules, code-mixing, tarnishing language quality, language shift, and language endangerment. Yet, the advantages obtained from the multidimensional appreciation of multilingualism overwhelm the disadvantages, which constitutes the motivation in developing this chapter. The review of most of the empirical research and evidence(s) that capture the varied claims of multilingual advantages is herein categorized (as indicated above) into two functional units: the individual and the societal (i.e., group, institutional, or national) multilingualism.
