His estimate of the social relations is given in the forty-sixth chapter, in which he says: “The married state is the great relation of mankind. One should not live alone after sixteen years of age, but should procure a mediator and perform the ceremony of matrimonial alliance. The same kindred, however, may not intermarry. A family of good descent should be chosen to marry into; for when a line of descendants is prolonged, the foreheads of ancestors expand. All mankind recognize marriage as the first law of nature.” The old custom of servants and retainers following their masters to death, and committing suicide in order to accompany them, is referred to in the seventy-fifth chapter.(257) It is not improbable that some exhibition of this custom occasionally was seen in the days of Ieyasu, for he very sternly condemns it thus: “Although it is undoubtedly an ancient custom for a vassal to follow his lord to death, there is not the slightest reason in the practice.... These practices are strictly forbidden, more especially to primary retainers, and also to secondary retainers even to the lowest. He is the opposite of a faithful servant who disregards this prohibition; his posterity shall be impoverished by the confiscation of his property, as a warning to those who disobey the laws.”(258) It is not necessary to follow in detail the line of Tokugawa shōguns. Few of them impressed themselves in any marked manner on the history of their country. Iemitsu, the third shōgun, who was a grandson of Ieyasu, was a man of great ability, and left many marks of his talents upon the empire. Under his administration the capital made great advances. He bound the daimyōs to his house by requiring them to maintain residences in Yedo under the surveillance of the government. His mausoleum is placed with that of his grandfather amid the august glories of Nikkō. Tsunayoshi (1681-1709) during his incumbency was more than usually interested in the peaceful prosperity of his country, and is gratefully remembered for his patronage of education and letters. But on the whole they were content to fill the office of shōgun in a perfunctory manner, and to leave to subordinates the duty of governing. Japan reached the acme of her ancient greatness during the Tokugawa dynasty. The arts which have given her such a deservedly high rank attained their greatest perfection. Keramics and lacquer, which are her most exquisite arts, achieved a degree of excellence to which we can now only look back with hopeless admiration. Metal-work, as shown in the manufacture of bronze and in the forging and mounting of swords, was scarcely less notable. The still higher art of painting, which came to Japan from China, rose during the Tokugawa period to the rank which it still holds in the estimation of the artistic world.