Page:The complete works of Henry George vol. 1.djvu/527

 human existence can be maintained with a smaller expenditure of force, and from a much smaller area, men can keep closer together, and the mental power which can at first be devoted to improvement is much greater. Hence civilization naturally first arises in the great valleys and table lands where we find its earliest monuments.

But these diversities in natural conditions, not merely thus directly produce diversities in social development, but, by producing diversities in social development, bring out in man himself an obstacle, or rather an active counterforce, to improvement. As families and tribes are separated from each other, the social feeling ceases to operate between them, and differences arise in language, custom, tradition, religion—in short, in the whole social web which each community, however small or large, constantly spins. With these differences, prejudices grow, animosities spring up, contact easily produces quarrels, aggression begets aggression, and wrong kindles revenge. And so between these separate social aggregates arises the feeling of Ishmael and the spirit of Cain, warfare becomes the chronic and seemingly natural relation of societies to each other, and the powers of men are expended in attack or defense, in mutual slaughter and