624 THE IDEALISTIC REACTION. We have elsewhere discussed the more recent attempts to establish a metaphysic which shall be empirically well grounded and shall cautiously rise from facts.* In regard to the possibility of metaphysics three parties are to be distinguished : On the left, the positivists, the neo-Kan- tians, and the monists of consciousness, who deny it out of hand. On the right, a series of philosophers — e. g., adherents of Hegel, Herbart, and Schopenhauer — who, without making any concessions to the modern theory of knowledge, hold fast to the possibility of a speculative metaphysics of the old type. In the center, a group of thinkers who are willing to renounce neither a solid noetical foundation nor the attainment of metaphysical conclusions — so Eduard von Hartmann, Wundt,f Eucken, Volkelt (pp. 590,617). Otto Liebmann (born 1840; On the Analysis of Reality, 1876, 2d ed., 1880; Thoughts and Facts, Heft i. 1882) demands a sharp separation between the cer- tain and the uncertain and an exact estimation of the degree of probability which theories possess ; puts the prin- ciples of metaphysics under the rubric of logical hypoth- csis; and, in his Climax of the Theories, 1884, calls attention to the fact that experiential science, in addition to axioms necessarily or apodictically certain and empeiremes possess- ing actual or assertory certainty, needs, further, a number of " interpolation maxims," which form an attribute of our type of intellectual organization {i.e., principles, according to the standard of which we supplement the fragmentary and discrete series of single perceptions and isolated observa- tions by the interpolation of the needed intermediate links, so that they form a connected experience). The most important of these maxims are the principles of real identity, of the continuity of existence, of causality, and of the continuity of becoming. Experience is a gift of the understanding ; the premises, as a rule, latent in ordinary
- R. Falckenberg, Ueber die gegenwartige Lagt der deutschen Philosofkie,
inaugural address at Erlangen, Leipsic, 1890. fWundt : Essays, 1885, including "Philosophy and Science"; System oj Philosophy, 1889. On the latter cf. Volkelt's paper in the Philosophische Monatshefie, vol. xxvii. 1891 ; and on the Essays a notice by the same author in the same review, vol. xxiii. 1887.
