Preface - Visual Illusions: Their Causes, Characteristics and Applications

by Matthew Luckiesh

A Random Illusion
Courtesy of Illusion-Optical.com

A message from the Editor:

This book, published in 1922, is a report on the applied science of optical illusions or visual illusions as they were called then.

It was written by Matthew Luckiesh, Director of Applied Science, NELA Research Laboratories, National Lamp Works of General Electric Co. Some of the research done by Mr. Luckiesh was conducted during "The Great War." Their task was to find the best ways to camouflage ships and airplanes.

He wrote this book because there didn't appear to be any other optical illusions book available which treated "the subject in a condensed manner but with a broad scope."

We hope you enjoy this incredible book on Optical Illusions.

Preface

EVENTUALLY one of the results of application to the analysis and measurement of the color, vision, lighting and light phenomena is a firmly entrenched conviction of the inadequacy of physical measurements as a means for representing what is perceived.

Physical measurements have supplied much of the foundation of knowledge and it is not a reflection upon their great usefulness to state that often they differ from the results of intellectual appraisal through the visual sense. In other words, there are numberless so-called optical illusions which must be taken into account. All are of interest; many can be utilized; and some must be suppressed.

Scientific literature yields a great many valuable discussions from theoretical and experimental viewpoints but much of the material is controversial. The practical aspects of optical illusions have been quite generally passed by and, inasmuch as there does not appear to be a volume available which treats the subject in a condensed manner but with a broad scope, this small volume is contributed toward filling the gap.

Here the complexity of this subject, which is extreme, is well recognized, but an attempt toward simplicity has been made by confining discussions mainly to static optical illusions, by suppressing minor details, and by subordinating theory. In other words, the intent has been to emphasize experimental facts. Even these are so numerous that only the merest glimpses of various aspects can be given in order to limit the text to a small volume. Some theoretical aspects of the subject are still extremely controversial, so they are introduced only occasionally and then chiefly for the purpose of illustrating the complexities and the trends of attempted explanations. Space does not even admit many qualifications which may be necessary in order to escape criticism entirely.

The optical illusions discussed are chiefly of the static type, although a few others have been introduced. Some of the latter border upon motion, others upon hallucinations, and still others produced by external optical media are optical illusions only by extension of the term. These exceptions are included for the purpose of providing glimpses into the border lands.

It is hoped that this condensed discussion, which is ambitious only in scope, will be of interest to the general reader, to painters, decorators, and architects, to lighting experts, and to all interested in light, color, and vision. It is an essential supplement to certain previous works.