Page:Collected Works of Dugald Stewart Volume 1.djvu/20

2 to point out their most important defects,—defects which, I am nevertheless very ready to acknowledge, it is much more easy to remark than to supply. The critical strictures which, in the course of this discussion, I shall have occasion to offer on my predecessors, will, at the same time, account for my forbearing to substitute a new map of my own, instead of that to which the names of Bacon and D'Alembert have lent so great and so well-merited a celebrity; and may perhaps suggest a doubt, whether the period be yet arrived for hazarding again, with any reasonable prospect of success, a repetition of their bold experiment. For the length to which these strictures are likely to extend, the only apology I have to offer is the peculiar importance of the questions to which they relate, and the high authority of the writers whose opinions I presume to controvert. Before entering on the main subject, D'Alembert is at pains to explain a distinction, which he represents as of considerable importance, between the Genealogy of the sciences, and the Encyclopedical arrangement of the objects of human knowledge. "In examining the former," he observes, "our aim is, by remounting to the origin and genesis of our ideas, to trace the causes to which the sciences owe their birth; and to mark the characteristics by which they are distinguished from each other. In order to ascertain the latter, it is necessary to comprehend, in one general scheme, all the various departments of study; to arrange them into proper classes; and to point out their mutual relations and dependencies." Such a scheme is sometimes likened by D'Alembert to a map or chart of the intellectual world; sometimes to a genealogical or encyclopedical tree, indicating the manifold and complicated affinities of those studies, which, however apparently remote and unconnected, are all the common offspring of the human understanding. For