Aristotle's Politics is a textbook in Harvard Law school. The King Edward professor of English at Cambridge University invites his students to devote a term to what our colleges style the intensive study of Poetics. Formal logic can still be learned sufficiently well from Aristotelian Organon. The Rhetoric would be generally acknowledged to be one of best extant textbooks of subject. Mill, Sidgwick, Leslie Stephen, and other modern moralists still quote Ethics, not merely as a historical document, but for substantive ideas, and valid distinctions. In these domains experience of Greeks and his own observation provided sufficient material for Aristotle's schematizing, organizing, and analytic mind, and his results, though modifiable by our wider experience, can never be wholly superseded. In physical sciences, with partial exception of descriptive biology (the natural history of animals, etc.), logical mill ground in vacuo. Aristotle's physical treatises could never, like Ethics and Poetics, be profitably studied for their content, by large classes of students. The De Caelo, as leading up to cosmogony of Dante and Middle Ages, has a certain historic interest. If De Anima retains all its significance, it is because psychology is not, and never will be, a progressive as chapter on subject in Professor Thomson's Outline of Science is enough to show. But modern knowledge has so far superseded Physics, Generation and Decay, and Meteorology that their interest, even for history of is but slight, unless we stretch term to cover metaphysics. Only a student of metaphysics can be edified by spectacle of so keen and high-soaring an intelligence beating in void its wings in vain. Ignorant of facts and principles familiar to every modern schoolboy student of fourteen weeks in science, Aristotle imperturbably deduces from a priori assumptions and synonyms and idioms of Greek language a general philosophy of what would now be