PHILOSOPHICAL PERIODICALS. 287 approximation. Proof by appeal to unmusical persons, and to conso- nance of successive tones. But if consonance or degree of fusion is ' fusibility,' that relation of tones to one another which conditions fusion, there need be no quarrel between the two theories. Stumpf s synergy, invented ad hoc, makes way for the hypothesis that consonance is an unconscious coincidence manifesting itself in conscious satisfaction. Detailed discussion of Stumpf's counter-arguments.] W. von Zehender.
- Die unbeweisbaren Axiome.' [We learn the axioms in childhood ; we
accept them later because of their invariable fulfilment. They are 4 apodictically ' demonstrable, i.e., capable of a demonstratio ad oculos, and only logically indemonstrable. The meaning of every word depends on an implicit judgment of invariability.] A. Poetsch. ' Ueber Farben- vorstellungen Blinder.' [Introspective record, with comparisons, by a subject blind from her third year. Colours remain as memory images, with well-marked affective differences. There then occurs a transference of them, by feeling association, to other contents. Conscious memories of coloured scenes are wanting, and surrogate ideas take their place. Clangs are most easily associated with the colour-images ; pressure holds second place ; temperature associations are rare, and movement associa- tions unknown to the writer. Smell may connect with colour through touch ; taste associations are doubtful. There are great individual differ- ences among the blind in the matter of colour images ; many combat them of set purpose, as useless in practical life.] J. von Kries.
- Ueber die anomalen trichromatischen Farbensysteme.' [Experiments
to show that the anomalous trichromatic systems are not explicable as due to unusually intense and widely extended pigmentation. In the two cases reported, no weakness of the colour sense was found.] Literatur- bericht. Bd. xix., Heft 2 und 3. S. Witasek. ' Ueber die Natur der geometrisch-optischen Taeuschungen.' [Attempts, not to give a new explanation, but to bring out the essential difference between the
- psychological ' and the ' physiological ' modes of explanation. Critique
of Wundt, Einthoven, Stoehr. The judgment hypothesis (psychological explanation) : neither the judgment of comparison nor that of designa- tion (the two forms involved) is adequate to the facts of illusion. The sensation hypothesis (or perceptual idea hypothesis : physiological explanation), and its relation to the apprehension of two-dimensional space. Experiments : Stereoscopic examination of Zoellner's illusion ; the question of subliminal displacements. Result : This and cognate illusions are 'physiological,' not 'psychological,' in origin.] J. von Kries. ' Kritische Bemerkungen zur Farbentheorie.' [Criticism of recent papers by Hering, Hess and Tschermak.] W. von Zehender. ' Vernunft, Verstand und Wille.' [Reason, through the mediation of sense, furnishes us with knowledge ; understanding discovers likenesses and differences, and points them out to reason. Will is the executive of both faculties, and is shaped by experience. Illustration from the child's acquisition of speech, and of the power to read and write.] Besprechung. T. Ziehen. 'Kritischer Bericht ueber wichtigere Arbeiten auf dein Gebiete der Physiologie des Centralnervensystems der Wirbelthiere.' Literaturbericht. ZEITSCHRIFT FUR PHILOSOPHIE UND PHILOSOPHISCHE KRITIK. August, 1898. Rudolf Eucken. ' Die Stellung der Philosophic zur religiosen Bewegung der Gegenwart.' [This has already appeared in French in the Revue de- Metaphysique et de Morale for July, 1897.1 H. Siebeck.
- Die Willenslehre bei Duns Scotus und seinen Nachfolgern.' [A plain
historical account of the teaching of the School on the will and its free- dom during that period which is miscalled " the decline of Scholasticism ".
