Why are our pictures puzzles? Book

Seeing is complicated: our eyes are always moving, in part because the center of our gaze receives no light, the optic nerve connection blocks that. Our brain takes in the various light-sensing information and processes different levels of information to compose what we 'see'. The image is upside down, and the brain puts it back. Localized brain damage, such as a lesion, can cause some incredible visual problems for its victims.
Some elements of the eye are sensitive to motion, and others handle various elements of color and compare their data to arrive at what 'color' is.
For a long time, painters explored how and why we perceive primary colors. In parallel, scientists were trying to determine the same things. It was a while before it was discovered that the secret to "Why red, green, blue" was not out there but in ourselves.
The Impressionists dealt with elements of perception, color, motion, hue, contrast, luminance, in ways that shocked their contemporaries but showed deep insight into vision. They weren't just dabbing paint on a canvas, they were exploring color, motion, shimmer, and the moment captured in the eye.
This is a terrific book. It helps me understand the Impressionists, all art, and visual elements in nature better. After many trips to the Barnes, I can go back now with a sharper eye.
10/14/13 Addendum: There will be a new edition, with updated and added content, coming out in March 2014. I am looking forward to reading this again.