Short answers, pulled from the story.
The frontage displays text written in eleven of that nation's twelve official languages. This visual evidence anchors a complex definition where multilingualism simply means using more than one language by an individual or group.
A.J. Aitken noted this debate in The Oxford Companion to the English Language published by Oxford University Press in 1992. Scholars often disagree whether Scots is a language in its own right or merely a dialect of English.
Vivian Cook argued since 1992 that most multilingual speakers fall somewhere between minimal and maximal definitions. She calls these individuals multi-competent rather than fully fluent in every sense.
Noam Chomsky proposed the human language acquisition device as a mechanism enabling learners to recreate rules used by surrounding speakers. He uses this theory to explain poor results some adolescents have when learning aspects of a second language because the device is not normally available by puberty.
Authors state Switzerland's GDP is augmented by 10% due to multilingualism. That same study linked multilingualism to firm productivity and gross domestic production.