[98] For a summary of these investigations, see the chapter “Sensations of Orientation” in Prof. E. Mach’s Popular Scientific Lectures, 3rd ed., Chicago, 1898; and for original discussions of the whole subject of space-sensations, see the same author’s Analysis of the Sensations, Chicago, 1897.—Trans.
[99] Münsterberg, Beiträge zur experimen. Psychologie, pp. 182 et seq. Wundt, Physiol. Psychologie, 4th ed., II. pp. 95-96.
[100] This is not the place to enter into the well-known discussion between the “nativists” and the “empiricists.” To the former all sensation, visual or tactile, contains from its outset a quantum of extension which is the primitive element, and the foundation for our spatial constructions. For the others there are only local signs, tactile or visual, and movements whose synthesis suffices to constitute all the modalities of existence. Whichever hypothesis be adopted, the extension in point is always that given by concrete data (not that of space conceived in the abstract)—directly cognised according to some, a genetic construction according to others. This discussion has no direct relation with our subject: for the full debate see Ribot’s Psychologie allemande contemporaine, Ch. V. James (Psychology, II. Ch. XX.) has recently taken up the nativistic theory, giving new arguments in its favor.
[101] Extracted from Spencer’s Psychology, Vol. I. § 90.
[102] Lotze, Mikrokosmus, II. p. 47.
[103] Stallo, Concepts of Modern Physics, Chap. XIII., p. 225, Int. Sc. Ser., third ed. He also gives a very concise criticism of Mill’s theory of induction in geology.
[104] System of Logic, I. Bk. II., Chap. 15, § 1.
[105] The complete history of this question, from its first beginnings to contemporaneous work, may be studied in Nichols’s “Psychology of Time,” Am. J. of Psychol., III. pp. 453-530.
[106] For these and the following experiments, cf. Wundt, Physiologische Psychologie, 4th ed., I. pp. 408 et seq.
[107] Psychol., I. 642.