(4) Under monogamy, moreover, all family relationships are more definite and strong, and thus family bonds, and ultimately social bonds, are stronger. In the polygynous household the children of the different wives are half brothers and half sisters, hence family affection has little chance to develop among them, and as a matter of fact between children of different wives there is constant pulling and hauling. Moreover, because the children in a polygynous family are only half brothers this immensely complicates relationships, and even the line of ancestors. Legal relations and all blood relationships are, therefore, more entangled. It is no inconsiderable social merit of monogamy that it makes blood relationships simple and usually perfectly definite. All of this has an effect upon society at large, because the cohesive power of blood relationship, even in modern societies, is something still worth taking into account. But of course the main influence of all this is to be found in the family group itself, because it is only under such simple and definite relations as we find in the monogamous family that there is ample stimulus to develop the higher family affections. (5) From all this it follows that monogamy favors the development of high types of religion and morals, family affection being an indispensable root of any high type of ethical religion. That form of the family which favors the development of the highest type of this affection will, therefore, favor the development of the highest type of religion. We see this even more plainly, perhaps, in ancient times than in the present time, because it was monogamy that favored the development of ancestor worship through making the line of ancestors clear and definite, and thus monogamy helped to develop this type of religion, which became the basis of still higher types. (6) Monogamy not only favors the preservation of the lives of the children, but also favors the preservation of the lives of the parents, because it is only under monogamy that we find aged parents cared for by their children to any extent. Under polygyny the wife who has grown old is discarded for a young wife, and usually ends her days in bitterness. The father, too, under polygyny is rarely cared for by the children, because the polygynous household has never given the opportunity for close affections between parents and children. That monogamy, therefore, helps to lengthen life through favoring care of parents by children in old age is an element in its favor, for it adds not a little to the happiness of life, and so to the strength of social bonds, that people do not have to look forward to a cheerless and friendless old age.