“Plurality of languages: [...] It is crucial 1. that there are many languages and that they differ not only in vocabulary, but also in grammar, and so in mode of thought and 2. that all languages are learnable.”
-Hannah Arendt, Denktagebuch, i.e. Thinking Diary, p. 42f
I am convinced that Hannah Arendt is one of the philosophical thinkers who is most attuned to what is required of those who wish to achieve and sustain a genuinely democratic society. In the quote above, taken from the blog published by The Hannah Arendt Center at Bard College, Arendt talks about the benefits of a "plurality of languages."
In fact, it is plurality itself (in language and in all things) that is most vital to life. This is evident in the natural world, which sustains our own. It is visible in our world, too. The hope that all the workings of our society can be reduced to a single set of defined values is one of the "origins of totalitarianism."
In the natural world, diversity and plurality make possible the life-sustaining web of life. In our world, plurality makes possible (though it does not guarantee) the existence of the democratic freedom that we rightly prize so highly. At least, that we "theoretically" prize so highly.