[199] That the appearance of mental activity here is real can be proved by suggesting to the 'hypnotized' somnambulist that he shall remember when he awakes. He will then often do so. [200] For more details, cf. Malebranche, Rech. de la Verité, bk. iii, chap. i; J. Locke, Essay conc. H. U., book iii, ch. i; C. Wolf, Psychol. rationalis, § 59; Sir W. Hamilton, Lectures on Metaph., lecture xvii; J. Bascom, Science of Mind, § 12; Th. Jouffroy, Mélanges Philos., 'du Sommeil'; H. Holland, Chapters on Mental Physiol., p. 80; B. Brodie, Psychol. Researches, p. 147; E. M. Chesley, Journ. of Spec. Phil., vol. xi, p. 72; Th. Ribot, Maladies de la Personnalité, pp. 8-10; H. Lotze, Metaphysics, § 533. [201] L'Automatisme Psychologique, Paris, 1889, _passim_. [202] See his articles in the Chicago Open Court, for July, August and November, 1889. Also in the Revue Philosophique for 1889 and '90. [203] This whole phenomenon shows how an idea which remains itself below the threshold of a certain conscious self may occasion associative effects therein. The skin-sensations unfelt by the patient's primary consciousness awaken nevertheless their usual visual associates therein. [204] See Proceedings of American Soc. for Psych. Research, vol. i, p. 548. [205] Proceedings of the (London) Soc. for Psych. Research, May, 1887, p. 268 ff. [206] M. Janet designates by numbers the different personalities which the subject may display. [207] How to conceive of this state of mind is not easy. It would be much simpler to understand the process, if adding new strokes made the first one visible. There would then be two different objects apperceived as totals,--paper with one stroke, paper with many strokes; and, blind to the former, he would see all that was in the latter, because he would have apperceived it as a different total in the first instance. A process of this sort occurs sometimes (not always) when the new strokes, instead of being mere repetitions of the original one, are lines which combine with it into a total object, say a human face. The subject of the trance then may regain his sight of the line to which he had previously been blind, by seeing it as part of the face. [208] Perception of Space and Matter, 1879, part ii, chap. 3. [209] For a very good condensed history of the various opinions, see W. Volkmann von Volkmar, Lehrbuch d. Psychologie, § 16, Anm. Complete references to Sir W. Hamilton are given in J. E. Walter, Perception of Space and Matter, pp. 65-6. [210] Most contemporary writers ignore the question of the soul's seat. Lotze is the only one who seems to have been much concerned about it, and his views have varied. Cf. Medicinische Psychol., § 10. Microcosmus, bk. iii, ch. 2. Metaphysic, bk. iii, ch. 5. Outlines of Psychol., part ii, ch. 3. See also G. T. Fechner, Psychophysik, chap. xxxvii. [211] I purposely ignore 'clairvoyance' and action upon distant things by 'mediums,' as not yet matters of common consent.