The elements of experience and their integration, or modalism / by Henry J. Watt.

  • Henry J. Watt
Date:
1911
Catalogue details

Licence: In copyright

Credit: The elements of experience and their integration, or modalism / by Henry J. Watt. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

    89/96 (page 300)
    -concede that the brain could not possibly contain mechanisms of that peculiar kind which our analysis demands. Those who are sceptically or critically inclined will,, therefore, find it hard to abandon the parallel- istic view, however strong the evidence against it may be. This evidence has been recently gathered by W. McDougall and has been admirably expounded in his works, especially in his paper “ On the Relations of Corresponding Points of the Two Retinae1,5’ and in his book Body and Mind (Methuen, London, 1911). McDougall attempts with the help of the typical, and, of all, the best studied, example of binocular vision to show that for certain aspects of psychical states^ generally their unity amidst diversity of content—no physical correlative is known or conceivable. I propose briefly to state his arguments and general conclusion in favour of interactionism, and to urge certain considerations w7hich seem to me to make the facts still compatible with the demands for correlation and consequently with the broader views of parallelism. The arguments are as follows2: (1) “Any illuminated surface appears no brighter (or but very slightly brighter) in binocular than in monocular vision.” [Independence and equivalence.] (2) The facts of Fechner’s paradox. [Reconciliation of differences.] (3) An after-image is much more easily revived by stimulation of the eye it was formed in than of the other. [Independence.] (4) Binocular flicker disappears at the same rate of alternation of phases as does uniocular flicker and is practically independent of simultaneity or alternation of phases in the two eyes. [Independence and equivalence.] (5) The facts of flicker-rivalry and of the rivalry frequently observed in binocular colour-mixture and of the volitional predominance of either of two rival fields. [Failure or suppression of reconciliation.] (6) The independence of the two eyes with regard to the after-effects of seen movement. [Independence.] (7) The fusion of disparate points in binocular vision and the influence of practice thereon. [Reconciliation of differences.] (8) The acquired readjustment of corresponding points in certain cases of squint. [Ditto.] (9) “Perhaps the strongest evidence against the ‘common centre’ is afforded by the facts of functional blindness of one eye, whether occurring as a symptom of hysteria or induced by hypnotic suggestion.” “ But how is this dissociation or circumscription effected ? The subject himself knows nothing of the anatomy of his brain3.” (10) “ In certain rare cases a lesion of the visual cortex has produced a small area of blindness in one retina only : a fact fatal to the common view4.” [Independence.] 1 Brain, xxxm. 871 ff. 2 Op. cit. 872. The words in square brackets are added by me. 3 Op. cit. 3,2. 4 Op. cit. 292.