Baháʼu'lláh taught that the lack of a common language is a major barrier to world unity since the lack of communication between peoples of different languages undermines efforts toward world peace due to misunderstandings of language; he urged that humanity should choose an auxiliary language that would be taught in schools in addition to one's own native language, so that people could understand one another. He stated that until an auxiliary language is adopted, complete unity between the various parts of the world would continue to be unrealized.