This forceful volume, revised for publication under the editorship of Dr. Jacob Loewenberg, is announced as "heading the list" of Professor Royce's posthumous works. It consists of lectures delivered at Johns Hopkins University in 1906, under the title "Aspects of Post-Kantian Idealism." Very justly do its publishers say that it fills a genuine need in philosophical literature; that the idealistic doctrines of the self, the social order, nature and the Absolute are here presented with that power, clearness, and adequacy which Josiah Royce alone could summon to such a task. The reader is held to continuous admiration that so much could be accomplished within the brief compass of ten lectures, and that such clearness could be maintained when dealing thoroughly and fundamentally with matters usually so difficult. Professor Royce is surveying a field covered by many textbooks, as well as by his own previous volume on The Spirit of Modern Philosophy; but he is doing so with a different purpose. Here he presupposes that type of knowledge on the part of his reader. "In vain do we look," says Dr. Loewenberg, "for the hackneyed themes of a hundred histories of philosophy." The discussion addresses itself at once, then, to the more significant and vital problems, and easily surpasses in range and depth that which the books of the other type contain. To the advancing student of philosophical matters it must be a volume of very genuine service. -Ethics, Volume 31[1921]