eighteen months before he resumed them. He preserved a happier memory of his youthful essays in poetry in the wildest style of the Neapolitan school of Marino: a form of diversion, he says, almost necessary to the mind of the young when metaphysic has rendered it too subtle and too rigid in precisely those years when the ardour of youth ought to lead the mind into errors, so as to save it from becoming chilly and dry. This age, the "barbarism of intellect," vigorous in imagination and also, through the close connexion that exists between the two, in memory, requires to be nourished and exercised by the reading of poetry, history and rhetoric as well as by the study of languages. The art which it ought to learn is not criticism but "topic," the true art of the "_ingenium_" or faculty of invention. By means of this art children acquire materials which enable them to form sound judgments in later life; for sound judgment depends upon a complete knowledge of its subject-matter, and "topic" is the art of discovering the whole content of any given thing. In this way young people simply by following the course of nature become at once philosophers and good speakers. Some antidote is doubtless necessary to the exuberance of the imagination. But this must be sought in linear geometry rather than in logic: for geometry is to some extent pictorial in character, while it strengthens the memory by the great number of its elements, ennobles the imagination by the delicacy of its figures and stimulates the inventive faculty by forcing it to review all these figures in order to choose those suitable to the demonstration of the quantity required. But the whole value of geometry also was annulled by the method then in favour with the schools, the algebraic method; which like the scholastic logic numbs all the vigour of youthful faculties, obscures the imagination, enfeebles the memory, and renders the inventive power and the understanding sluggish; thus damaging the liberal arts in four distinct ways, in the knowledge of languages and history, in invention and in prudence. More particularly algebra is fatal to the inventive faculty, because in using the algebraic method one is conscious only of the immediate field of vision; it weakens the memory because once the second sign is found the first need no longer be remembered; it blinds the imagination, because that faculty is not used at all; it destroys the understanding, because it lays claim to the power of divination. Young men who have devoted their time to it on proceeding to deal with the affairs of civil life find themselves, to their great grief and remorse, unfitted for such a life. Hence, to make it useful in some degree and to prevent these ill effects, it should be studied for a short time only at the close of the mathematical course, and employed only as a means of abbreviation. The habit of reasoning is formed much better by metaphysical analysis, which in all questions begins by