The Wealth of Nations by Part 3 Chapter 4 Page 13

The introduction of the feudal law, so far from extending, may be regarded as an attempt to moderate the authority of the great allodial lords. It established a regular subordination, accompanied with a long train of services and duties, from the king down to the smallest proprietor. During the minority of the proprietor, the rent, together with the management of his lands, fell into the hands of his immediate superior, and, consequently, those of all great proprietors into the hands of the king, who was charged with the maintenance and education of the pupil, and who, from his authority as guardian, was supposed to have a right of disposing of him in marriage, provided it was in a manner not unsuitable to his rank.

But though this institution necessarily tended to strengthen the authority of the king, and to weaken that