We might compare in this respect the three great culture areas of the old world—Europe, India and China. The Chinese afford an instance of one relatively pure race occupying a very large area. In spite of its early start and great mental capacities, its culture has stagnated. The stock was perhaps too pure. India on the other hand seems to owe its peculiar history largely to the fact that its population in almost all parts has been made up from very widely different races—white, yellow and black; the heterogeneity has been too great for stability and continued progress. In Europe different branches and sub-branches of the white race, that is of stocks not too widely different in constitution, have undergone repeated crossing and recrossing. It is worth while to point out that, if our generalisation is valid, it follows that race-blending has been an important factor in the progress of civilisation. And the generalisation has also an important bearing upon one of the most urgent problems confronting the statesmen of the world at the present time, and not only the statesmen but all the citizens of the civilised states, especially the citizens of the British Empire and of America. For it justifies abundantly the refusal of the white inhabitants of various countries to admit immigrants of the yellow or negro race to settle among them; and it justifies, and more than justifies, the objection to intermarriage with those other races which Englishmen have upheld wherever they have settled, and which most other peoples have not upheld[120]. In all the currents of heated discussion as to the rights and wrongs of the treatment of other races, this question of the kind of subrace which will result from intermarriage is generally left in the background; whereas its importance is far greater than that of all other considerations taken together. Some, like Sir S. Olivier[121], are content to approve race-blending on the ground that it improves the inferior race. But the racial qualities of the leading peoples of the world are too precious to be squandered in the process of improving in some uncertain degree the quality of the overwhelming mass of humanity of inferior stocks; the process would probably result in the total destruction of all that humanity has striven and suffered for in its nobler efforts.