HUME'S CONTRIBUTION TO THE HISTORICAL METHOD.
OF all the progress which attended modes of scientific explanation during the nineteenth century, no single concept was developed, probably, which was comparable in importance for philosophical thought to the elaboration of the historical or evolutionary method. The essence of this method is the conception of historical continuity. Every institution, social or political, every art, science, or religion, in fact, everything which is the product of human activity, as well as every race or nation, has a history and is to be adequately understood only by a study of its genesis and course of development. A nation or institution as it exists at any single period, however self-sufficing it may be, is, so to speak, a cross-section of a long process which extends both into the past and into the future; though itself an individual, it is a member of a larger individual which extends beyond the limits of any single time. Moreover,—and this is the real meaning of historical continuity,—a series of historical events is a true individual. A mere succession of events in time is by no means adequate to form an historical sequence; a thread of connection, a relating principle, must run through all the particular events and give them a unity in the light of which alone the particular event can have any significance. History deals always with the progress or decadence of a unitary being which persists as an individual in spite of changes; it never deals with a collection of sequent but unrelated events. Unless this were the case, any fact would be of equal importance to the historian with every other fact; selection can take place only with reference to a universal.
Along with this conception of historical evolution, and perhaps preceding it somewhat in point of time, has arisen the notion of social solidarity. Not only is society continuous in its development but it is an organic unit at any given time. Its parts exist in such a relationship that any considerable change in
