Herein we see a repetition, but on a small scale, of the Saxon colonization of England. The settled communities established by the Scotch pioneers sheltered and nursed the national spirit they brought with them. As the fringe of colonists expanded it came to cover Antrim and Down and made inroads on adjacent counties, overwhelming and absorbing the tribal organization of the native population. In 1672 Sir William Petty estimated that there were 100,000 Scots in Ulster. Thus in the north-east of Ireland there has been established a people which manifests all the qualities of a new nationality. History can explain to us how it has come about that the inhabitants of Ireland, all of them derivatives of the same breed of Europeans, should be divided into two peoples, each possessed by its own peculiar sense of nationality. The north is predominantly industrial and Protestant; the south is predominantly pastoral and Catholic. But these circumstances are not sufficient to account for a national--almost a racial--antagonism between the inhabitants of a single small island who have so much to gain by a sense of unity. To understand national antagonisms we have to look at the inheritance which modern man has carried with him from his distant past. THE NATURE OF TRIBAL INSTINCT I now enter the third stage of my argument. In the first I cited and discussed the various forms in which racial and national feelings are manifested by various peoples abroad; in my second I dealt with the nature of the various national movements at home. We now set out in search of the root from which the flower of our complex modern civilization has sprung. In the world of to-day we see many peoples exhibiting every phase in the evolution of that organization which permits mankind to live in massed populations. Fortunately for us there yet survive, in outlandish parts of the earth, remnants of native races retaining the primitive organization which guided mankind through that great hinterland of time lying between the emergence from apedom and the dawn of the modern world. For the student of sociology the immense primitive first stage of man's history is by far the more important. In his _Voyage of the Beagle_, Darwin draws a picture of the Fuegians which gives us a real insight into the ancient state of social organization. Spencer and Gillan supply us with complementary pictures representing the conditions of life among native tribes of Central Australia. These primitive peoples live on the natural produce of the territory which they inhabit and claim as their own. Their social organization represents for us the conditions in which the modern races of mankind were evolved. It is in such primitive societies that there must have existed the machinery which differentiated mankind into races and racial breeds. It is in the long first phase that we must search for the origin of the social impulses and tendencies which have come down to modern man by inheritance.[1]