Page:Mind (New Series) Volume 8.djvu/155

 PHILOSOPHICAL PERIODICALS. 141 und Gefuehlscontrast.' [The ' law ' of contrast in Hoeffding, Wundt r Fechner, etc., demands a detailed examination. (1) Perceptual con- trast. Sense contrasts obtain only in the sphere of vision ; their explana- tion is physiological. Perceptual contrast is due to the departure of a perception from the mean of experience ; this produces a ' contrast feeling,' of surprise or disappointment, which is added to the (unaltered) perceptual contents. Apparent exceptions are accounted for by modifica- tion of memory-images. (2) Affective contrast as co-ordinate with colour contrast. Critique of Hoeffding. (3) Affective and perceptual contrast. Feeling, as subjective, cannot ' seem ' to be weaker or stronger, as objective perceptions can ; and, dependent as it is on the total mental state, cannot come into conflict with a pre- existent feeling-tendency. The introduction of secondary feelings, resulting from the effort after feeling, gives no assistance towards the explanation of affective contrast. But when perceptions contrast, the contrast feeling arises : and this is a special case of affective contrast at large. When our attention is on the objects, we speak of perceptual contrast ; when the contrasting objects are so related as to arouse strong feelings of opposite quality, of affective : there are all stages.] W. von Zehender. ' Ueber die Entstehung des Raumbegriffes.' [The ideas of space, time and God are,, in germ, a priori in human nature ; but experience, outer and inner, is. necessary to their realisation.] K. Ebhardt. ' Zwei Beitraege zur Psychologic des Rhythmus und des Tempo.' [(1) If taps are made, or tones played, in unaccented series, we find the duration of the intervals- subject to a variable error. Accentuation (rhythm) increases this variable, and introduces a constant error : the interval following an accent is made longer than that preceding. Explanation (for bimembral and trimembral rhythms) in terms of motor adjustment, change of direction of attention, composition and analysis of groups, and (in the tonal series) affective value. (2) Compositions are played on a soundless keyboard most slowly ; next most slowly, on the piano with- out accompaniment ; most quickly on the piano with both hands. Explanation in terms of amount of mental work involved (reproduction), and of relative speed of arousal of expected feelings.] Literaturbericht. Bd. xviii., Heft 3. O. Abraham und L. J. Bruehl. ' Wahrnehmung kuerz- ester Toene und Geraeusche.' [A series of siren experiments, notable for their range (contra to middle of c 4 octave) and for the fact that the subject is possessed of a reliable ' absolute ' tonal memory, gives the result that two vibrations suffice for a tone sensation and judgment of absolute pitch. From the a 4 to the a 5 the number of vibrations rises to ten. The absolutely least time (g*) is O63<r. The ' clap ' that results from the blowing of a single hole of the siren disc is a complex noise, conditioned by the primary wave, the distance of points of reflexion, and the periods of the after- vibrations.] K. Deffher. ' Die Aehnlichkeits- association.' [The two types of association : the original, by similarity ; and the acquired, by ' experience ' or contiguity. Critique of Hoeffding and Kuelpe. Similarity may obtain between conscious contents (two colours), or between the unconscious processes underlying these ('deep T tone and 'deep' colour). Exposition of this (Lipps') doctrine of associa- tion, with special reference to musical tones. The most convincing part of the discussion is, perhaps, the criticism of Kuelpe's association by feeling. Wundt's Bemerkungen should have been taken account of.] Literaturbericht. Bd. xviii., Heft. 4. H. Voeste. ' Messende Versuche ueber die Qualitaetsaenderungen der Spektralfarben in Folge von Ermue- dung der Netzhaut.' [Stimulation for ten sec. From red to 570^, the colour shifts towards violet ; at 560 pp there is no change ; thence to 500 /i/*.