[178] Nouveaux Essais, Avant-propos.
[179] J. S. Mill, Exam. of Hamilton, chap. xv.
[180] Cf. Dugald Stewart, Elements, chap. ii.
[181] J. E. Maude: 'The Unconscious in Education,' in 'Education,' vol. i, p. 401 (1882).
[182] Zur Lehre vor Lichtsinne (1878).
[183] Cf. Wundt: Ueber den Einfluss der Philosophie, etc.—Antrittsrede (1876), pp. 10-11;—Helmholtz: Die Thatsachen in der Wahrnehmung (1879), p. 27.
[184] Cf. Satz vom Grunde, pp. 59-65. Compare also F. Zöllner's Natur der Kometen, pp. 342 ff. and 425.
[185] Cf. the statements from Helmholtz to be found later in [Chapter XIII].
[186] The text was written before Professor Lipps's Grundtatsachen des Seelenlebens (1883) came into my hands. In Chapter III of that book the notion of unconscious thought is subjected to the clearest and most searching criticism which it has yet received. Some passages are so similar to what I have myself written that I must quote them in a note. After proving that dimness and clearness, incompleteness and completeness do not pertain to a state of mind as such—since every state of mind must be exactly what it is, and nothing else—but only pertain to the way in which states of mind stand for objects, which they more or less dimly, more or less clearly, represent; Lipps takes the case of those sensations which attention is said to make more clear. "I perceive an object," he says, "now in clear daylight, and again at night. Call the content of the day-perception a, and that of the evening-perception a1. There will probably be a considerable difference between a and a1. The colors of a will be varied and intense, and will be sharply bounded by each other; those of a1 will be less luminous, and less strongly contrasted, and will approach a common gray or brown, and merge more into each other. Both percepts, however, as such, are completely determinate and distinct from all others. The colors of a1 appear before my eye neither more nor less decidedly dark and blurred than the colors of a appear bright and sharply bounded. But now I know, or believe I know, that one and the same real Object A corresponds to both a and a1. I am convinced, moreover, that a represents A better than does a1. Instead, however, of giving to my conviction this, its only correct, expression, and keeping the content of my consciousness and the real object, the representation and what it means, distinct from each other, I substitute the real object for the content of the consciousness, and talk of the experience as if it consisted in one and the same object (namely, the surreptitiously introduced real one), constituting twice over the content of my consciousness, once in a clear and distinct, the other time in an obscure and vague fashion. I talk now of a distincter and of a less distinct consciousness of A, whereas I am only justified in talking of two consciousnesses, a and a1, equally distinct in se, but to which the supposed external object A corresponds with different degrees of distinctness." (P. 38-9.)