With a much enlarged and more varied conception of association, Alexander Bain reexecuted the general psychological task, while Herbert Spencer revised the doctrine from the new point of view of the evolution hypothesis. John Stuart Mill made only occasional excursions into the region of psychology proper, but sought, in his "System of Logic" (1843), to determine the conditions of objective truth from the point of view of the associationist theory, and, thus or otherwise being drawn into general philosophical discussion, spread wider than any one before him its repute. The Associationist School was composed chiefly of British thinkers, but in France also it had distinguished representatives. Of these it will suffice to mention Condillac, who professed to explain all knowledge from the single principle of association (liaison) of ideas, operating through a previous association with signs, verbal or other. In Germany, before the time of Immanuel Kant, mental association was generally treated in the traditional manner, as by Christian Wolff. Kant's inquiry into the foundations of knowledge, agreeing in its general purport with Locke's, however it differed in its critical procedure, brought him face to face with the newer doctrine that had been grafted on Locke's philosophy. To account for the fact of synthesis in cognition, in express opposition to associationism, as represented by Hume, was, in truth, his prime object, starting, as he did, from the assumption that there was in knowledge that which no mere association of experiences could explain. To the extent, therefore, that his influence prevailed, all inquiries made by the English associationists were discounted in Germany. Notwithstanding, under the very shadow of his authority a corresponding, if not related, movement was initiated by Johann Friedrich Herbart. As peculiar and widely different from anything conceived by the associationists as Herbart's metaphysical opinions were, he was at one with them and at variance with Kant in assigning fundamental importance to the psychological investigation of the development of consciousness. Further, his conception of the laws determining the interaction and flow of mental presentations and representations, when taken in its bare psychological import, was essentially similar to theirs. In Friedrich Eduard Beneke's psychology also and in more recent inquiries conducted mainly by physiologists, mental association has been understood in its wider scope, as a general principle of explanation. The associationists differ among themselves in the statement of their principle and, when they adduce several principles, in their conception of the relative importance of these. The highest philosophical interest, as distinguished from that which is more strictly psychological, attaches to the mode of mental association called Inseparable.