Returning to Malthus, we find him following an order of his own, in rough conformity with the orthodox progress from deer to sheep, and from sheep to corn. He takes us from Polynesian savages to the nomad pastoral nations of ancient Europe.[186] The vast migrations and their momentous historical effects he ascribes to the “constant tendency in the human race to increase” beyond its food, and thinks that when history has been rewritten it will contain more of this.[187] “The misfortune of history is, that while the particular motives of a few princes and leaders are sometimes detailed with accuracy, the general causes which crowd their standards with willing followers are totally overlooked.”[188] At first sight the phenomenon of civilized agricultural nations unable to repel the invasion of shepherds seems incredible; a country in pasture cannot possibly support so many inhabitants as a country in tillage. A shepherd, it is true, is nearer to the skilled labourer than a hunter; he does not simply take what nature gives him, where nature puts it; he keeps the desired objects of consumption under his own control, and his life is stronger because more social. Early African colonization, as Adam Smith pointed out, was less successful than early American, because the natives, being shepherds and even farmers rather than fishermen, were stronger in their resources and more united than the American aborigines, so that the European intruders were not able to displace them.[189] We should have expected the Scythian, Cimbrian, and Gothic invaders of ancient times to have had a similar rebuff. “But what renders nations of shepherds so formidable is the power which they possess of moving altogether, and the necessity they frequently feel of exerting this power in search of fresh pasture for their herds.”[190] They have always in their breeding stock a reserve of food for an emergency. The mere consciousness that their mode of life does not bind them to one place gives them less anxiety about providing for a family. Therefore, when they exhaust one region and begin to feel the pinch of want, they make an armed emigration on the scale of whole tribes at once, for the occupation of more fruitful regions, and, as a rule, the conquest of them by force. The law of their life is a series of periodical “struggles for existence”[191] between one nation and another, in which the fittest survive at the cost of a prodigious waste of human life.