Pleasure + effort-image = impulse.

[Footnote 1:  Among Fortlage’s other works we may mention his valuable History of Poetry, 1839; the Genetic History of Philosophy since Kant, 1852; and the attractive Six Philosophical Lectures, 1869, 2d ed., 1872.]

In his metaphysical convictions, to which he gave expression in his Exposition and Criticism of the Arguments for the Existence of God, 1840, among other works, Fortlage belongs to the philosophers of identity.  Originally sailing in Hegel’s wake, he soon recognizes that the roots of the theory of identity go back to the Kantio-Fichtean philosophy, with which the system of absolute truth, as he holds, has come into being.  He thus becomes an adherent of the Science of Knowledge, whose deductive results he finds inductively confirmed by psychological experience.  Psychology is the empirical test for the metaphysical calculus of the Science of Knowledge.  In regard to the absolute Fortlage is in agreement with Krause, the younger Fichte, Ulrici, etc., and calls his standpoint transcendent pantheism.  According to this all that is good, exalted, and valuable in the world is divine in its nature; the human reason is of the same essence as the divine reason (there can be nothing higher than reason); the Godhead is the absolute ego of Fichte, which employs the empirical egos as organs, which thinks and wills in individuals, in so far as they think the truth and will the good, but at the same time as universal subject goes beyond them.  If, after the example of Hegel, we give up transcendent pantheism in favor of immanence, two unphilosophical modes of representing the absolute at once result—­on the one hand, materialism; on the other, popular, unphilosophical theism.  If the Fichtean Science of Knowledge could be separated from its difficult method, which it is impossible ever to make comprehensible to the unphilosophical mind, it would be called to take the place of religion.[1]

[Footnote 1:  Among Fortlage’s posthumous manuscripts was one on the Philosophy of Religion, on which Eucken published an essay in the Zeitschrift fuer Philosophie, vol. lxxxii. 1883, p. 180 seq. after Lipsius had given a single chapter from it—­“The Ideal of Morality according to Christianity”—­in his Jahrbuecher fuer protestantische Theologie (vol. ix. pp. 1-45).  The journals Im Neuen Reich, 1881, No. 24, and Die Gegenwart, 1882, No. 34, contained warmly written notices of Fortlage by J. Volkelt.  Leopold Schmid (in Giessen, died 1869) gives a favorable and skillfully composed outline of Fortlage’s system in his Grundzuege der Einleitung in die Philosophie mit einer Beleuchtung der von K. Ph.  Fischer, Sengler, und Fortlage ermoeglichten Philosophie der That, 1860, pp. 226-357.  Cf. also Moritz Brasch, K.  Fortlage, Ein philosophisches Charakterbild, in Unsere Zeit, 1883, Heft II, pp. 730-756, incorporated in the same author’s Philosophie der Gegenwart, 1888.]