Kinsmen’s friendship seems to include several species, but to be dependent in all its forms upon the friendship of parent and child. For parents love their children as part of themselves; children love their parents as the source of their being. But parents know their children better than the children know that these are their parents, and that which gives birth is more closely attached to that which proceeds from it, than the offspring is to that which gave it life: for that which proceeds from us belongs to us, as a tooth or a hair, or anything of that sort, to its owner; but we do not belong to it at all, or belong to it in a less degree.

Again, there is a difference in respect of time; for parents love their offspring from the moment of their birth, but children love their parents only after the lapse of time, when they have acquired understanding or sense.

These considerations also show why mothers love their children more than fathers do.