A Natural History of Vision. Wade NJ. Cambridge, MA: MIT Press, 1998.
Those interested in the history of medicine and science are fortunate to have available several publications on the history of ophthalmology and of medicine, as well as on the history of optics. If you enjoy such works you will want to read A Natural History of Vision. This fascinating and wide-ranging book traces the development of philosophical and scientific thought in the field of vision, primarily during the centuries that preceded clinical and experimental research. This covers the span from ancient Greek science up to the mid-19th century, an era that the author refers to as the “observational era of vision.” (Subsequent developments opened the “experimental era.”)
Nicholas Wade presents this study as a documentary or narrative history, so that a large proportion of the text is devoted to direct quotations from the work of historical figures ranging from Aristotle and Euclid to Newton, Thomas Young, and Johann Wolfgang von Goethe. The chapters of the book comprise major topic areas of vision: Light and the Eye, Color, Subjective Visual Phenomena, Motion, Binocularity, Space, and Illusions. Within each chapter the various aspects of each topic are addressed. The author provides an introduction for each section in which he summarizes the views or theories of the writers whose work is quoted later in the section. Also provided is a historical background for each section that establishes the context for the subsequent statements by historical figures.
The introduction to the chapter “Light and the Eye” describes how the concept of vision involving “some copy of objects, carried through the air to the eye . . .” had “long-lasting appeal.” The terms used by writers on vision to describe these “copies” could be considered synonyms for “image.” The crystalline lens was long considered the “seat of vision.” Galen noted that blindness results from cataracts and vision is restored by their removal. It was probably Kepler (1604) who, on reading the treatises of Alhazen and Vitellonis, discerned a need for an optical description of the retinal image. He states that “vision occurs” when objects before the eye are imaged on the retina.
Kepler was also instrumental in the development of the study of light as a physical science. He described light rays as being emitted by a source and spreading in all directions. Soon he was followed by Snell, Descartes, and Huygens. With the study of light now the province of physicists, the study of vision was pursued by physiologists and philosophers.
In the chapter on Color, we learn that the concept of primary colors originated with Greek science and endured through the time of Newton. About 1666, Newton used a prism to demonstrate spectral colors and proposed his own theory on color and the structure of a color circle. Discussion of the nature of the primary colors led to interest in the processes responsible for color vision, including interest in color vision deficiencies. I was interested to learn that John Dalton, author of the atomic theory of matter, had deutanomalous color vision. He published a description of his color perception, and the condition became known as daltonism by the early nineteenth century. It was William Brewster in 1844 who coined the term color blindness to prevent the condition from being associated with Dalton, who was a scientist of considerable note.
In A Natural History of Vision, Nicholas Wade has given us fascinating first-hand accounts of the early development of our understanding of vision. The modest effort required of the reader who takes up this volume will be rewarded many times over.