Hooker seems to have perceived this, and in the discussion which followed the reading of Udny Yule's paper he set forth what (though it was not accepted by Udny Yule) may perhaps fairly be regarded as the sound view of the matter. "During the great expansion of trade prior to 1870," he remarked, "the means of satisfying the desired standard of comfort were increasing much more rapidly than the rise in the standard; hence a decreasing age of marriage and a marriage-rate above the normal. After about 1873, however, the means of satisfying the standard of comfort no longer increased with the same rapidity, and then a new factor, he thought, became important, viz. the increased intelligence of the people."[134] This seems to be precisely the same view of the matter as I have here sought to set forth; prosperity is not civilization, its first tendency is to produce a reckless abandonment to the satisfaction of the crudest impulses. But as prosperity develops it begins to engender more complex ideals and higher standards; the inevitable result is a greater forethought and restraint.[135] If we consider, not the marriage-rate, but the average age at marriage, and especially the age of the woman, which varies less than that of the man, the results, though harmonious, would not be quite the same. The general tendency as regards the age of girls at marriage is summed up by Ploss and Bartels, in their monumental work on Woman, in the statement: "It may be said in general that the age of girls at marriage is lower, the lower the stage of civilization is in the community to which they belong."[136] We thus see one reason why it is that, in an advanced stage of civilization, a high marriage-rate is not necessarily associated with a high birth-rate. A large number of women who marry late may have fewer children than a smaller number who marry early.