杏吧原创

The Science of Illusions by Jacques Ninio, translated by Franklin Philip,
Cornell University Press, 拢16.95/$25, ISBN 0801437709

DARK lodestones were male and light ones female. That鈥檚 why they clung
together, naturally attracted to each other. This original explanation of the
phenomenon faded as magnetism was accepted into the fold of physics. But
conflict between physics and psychology persists today in attempts to explain
optical illusions.

Jacques Ninio鈥檚 approach is individual and intuitive rather than rigorous.
The Science of Illusions is full of phenomena artists may find useful鈥攁nd
Ninio points out illusions that have confused scientists. It will appeal to
those who enjoy the view from the somewhat wobbly bridge between art and
science.

But this is more than just a collection of optical illusions. It鈥檚 a
thoughtful account of significant phenomena, not just visual, but also of the
senses of hearing and touch.

A brief history of visual perception takes us from the early idea that we see
by shooting light out of our eyes, to the discovery of the eye as an
image-forming instrument. This was first suggested by Al Hazan in the 10th
century, and Johannes Kepler confirmed the details early in the 17th
century.

Ninio refers to my own 鈥減eeriodic table of the elements of illusions鈥� when he
comes to classifying the pictures. It鈥檚 a hard task. If illusions are departures
from truth, what truths are accepted as references? Take a picture: do you
compare the lines of the picture with a ruler or with the features of the scene
the picture represents? Each gives a very different measure of illusion.

I welcomed the chapter on magic. Almost no books on the psychology of
perception discuss conjuring. As Ninio says, its power is amazing because the
principles of most conjuring tricks are well known. We know how mirrors work,
for example, yet are still fooled by them. What is so surprising is the
importance of selective attention. Conjurors have learned to control this way
beyond the understanding of psychology.