a thorough-going doubter, who, by means of his doubts, got rid of an accumulation of propositions, assumed on authority to be true,—the intellectual division, generalization, and argumentation of the contents of which formed the materiel of the preceding or scholastic epoch of philosophy. The Cartesian “scepticism” raked up the foundations of things, and during the lifetime of the philosopher himself, as well as since, it has communicated a corresponding impulse to meditative minds by whom his works have been studied. Des Cartes doubted in order to believe and know. From the foundation down to which his doubts conducted him, he attempted to rear a comprehensive theory of knowledge. But the reconstructive has exerted small influence compared to the destructive part of his teaching, and it is mainly through the operation of the latter element that a revolution in the manner of thinking regarding the first principles of every sort of knowledge is the permanent result of his labours.
The period of the history of human thought that has intervened since Des Cartes, is filled by a series of more or less imperfect reconstructions of philosophy, i.e., of the ultimate theory of knowledge,—out of the confusion consequent upon the sceptical method of the French philosopher. The attempt of Locke, in the “Essay concerning Human Understanding,” is the first of prominent historical importance. That great work is still properly an unfinished one. The metaphysical thinking of the last century and a half has been to a great degree employed in working out the problem suggested in it, which the
