A THEORY OF VISION

New Zealand Listener, Volume 26, Issue 660, 29 February 1952, Page 12

A THEORY OF VISION

HE CLAIRVOYANT THEORY OF PERCEPTION, by M. M. Moncrieff; Faber and Faber. English price, 21/-.

(Reviewed by

G. E.

Hughes

HAT happens when we see an external object? The usual view is that sight is the result of light waves reflected from the object impinging on the retinae of our eyes, thus stimulating the optic nerves and finally the visual areas of the brain. But this, Captain Moncrieff contends, involves

us in grave difficulties. For example, if sight is the endproduct of as complicated a _ process as this, there seems to be no guarantee -rather an extreme unlikelihood — that what we see in any way resembles the external object; again, how can we explain the fact that we see things as "out there" and not as somewhere inside our heads? Moreover. there is

an increasing body of evidence for what is usually called clairvoyance, i.e., visual awareness of objects which doesn’t seem to be obtained by means of the sense-organs at all, and it seems impossible to fit this into the conventional picture. Captain Moncrieff proposes to solve these and other difficulties by a new theory of vision which regards clairvoyance not as a rare freak but as the basic constituent even in ordinary vision. What ~-the theory in outline amounts to is this: we have the ability to be aware of things directly, just as they are. This ability does not necessarily depend on our visual organs; we occasionally exercise it independently of them, and perhaps some of the lower animals do so on a large scale; but obviously it would be highly inconvenient if we were continually aware of everything, and so in the course of evolution we have developed organs (eyes, optic nerves, etc.) of such a nature that in ordinary experience our power of seeing things directly comes into play only when these organs are stimulated. It would thus be truer to say that the function of our visual organs is to re- strict our vision to what we can conveniently deal with, rather than actually to produce sight. This is not an altogether original suggestion, but it is, I think, the first time it has been worked out with anything like the thoroughness and elaboration which Captain Moncrieff displays. It would be too much to say that I have been altogether convinced by his arguments, or that I find everything in the book as clear as I would like it to be; but I cannot help being impressed by the detailed ‘and painstaking way in which he sets out to show the compatibility of -his theory with the experimental evidence about vision. and by the advantages he claims for his theory over its rivals. Not the least of these advantages is that it enables us to hold that the qualities we see when we look at things really do belong

to them-even the notorious. colourqualities, which most theories regard as subjective; and this, to say the least, is highly flattering to common sense. (Captain M. M. Moncrieff has lived in New Zealand for 30 years. His book has attracted much notice from philosophers in England and in the United States.-Ed.)