Nature follows a similar process in developing the psychological unity of a societal grouping as in the development of living beings. Sri Aurobindo notes: “She has provided first a natural body, next a common life and vital interest for the constituents of the body, last, a conscious mind or sense of unity and a centre or governing organ through which that common ego-sense can realise itself and act.”
Elements that are like to one another or located in a geographic region that forms a natural landmass for the aggregate are the primary bonding causes. “In earlier times when communities were less firmly rooted to the soil, the first of thee conditions was the more important. In settled modern communities the second predominates; but the unity of the race, pure or mixed — for it need not have been one in its origin — remains a factor of importance, and strong disparity and difference may easily create serious difficulties in the way of the geographical necessity imposing itself with any permanence. In order that it may impose itself, there must be a considerable force of the second natural condition, that is to say, a necessity of economic unity or habit of common sustenance and a necessity of political unity or habit of common vital organisation for survival, functioning and aggrandisement. And in order that this second condition may fulfil itself in complete force, there must be nothing to depress or destroy the third in its creation or its continuance. Nothing must be done which will have the result of emphasising disunity in sentiment or perpetuating the feeling of separateness from the totality of the rest of the organism; for that will tend to make the centre or governing organ psychologically unrepresentative of the whole and therefore not a true centre of its ego-sense. But we must remember that separatism is not the same thing as particularism which may well coexist with unity; it is the sentiment of the impossibility of true union that separates, not the mere fact of difference.”
Sri Aurobindo cites as an example of a heterogeneous nation that developed a considerable sense of unity in the development of the British nation, what is now called the United Kingdom. “The British nation has been composed of an English-speaking Anglo-Norman England, a Welsh-speaking Cymric Wales, a half-Saxon, half-Gaelic English-speaking Scotland and, very imperfectly, very partially, of a Gaelic Ireland with a mainly Anglo-Scotch colony that held it indeed by force to the united body but was never able to compel a true union.” In fact, Ireland eventually gained its own status as an independent nation. It must also be noted that in recent years, the focus on Scottish independence and a focus on the psychological difference from the English core of the nation have gained substantial force, due in part to parliamentary process that tended to under-value the Scottish region (at least in the minds of those seeking Scottish independence) and the centrifugal force of this idea working to break up the integrity of the nation unit. As Sri Aurobindo pointed out, the ego-sense of the aggregate is under pressure through emphasis of differences rather than common goals, needs or geographical realities.
Sri Aurobindo, The Ideal of Human Unity, Part I, Chapter 7, The Creation of the Heterogeneous Nation, pp. 55-57