I enjoy reviewing books having to do with the sciences and the natural world. While The Secret Language of Color at first glance appears to be an art book, it is so much more. Not only does this book mesmerize the reader with spellbinding rainbow hues page after page; it also informs with historical, scientific and even social/political insight into the way nature (and humans) paint the world. Mother-daughter team Joann Eckstut and Arielle Eckstut set out to publish a book to help wed the art and science of color and came up with a masterpiece.
The authors' effort to understand color humbled them.
We thought we were color experts before we wrote this book, but we were brought to our senses by the breadth and depth of the material. Now we like to describe ourselves as color tourists who traveled the world of color -- its jungles, deserts, cities, forests, rural villages, seas, monuments, and museums -- and made it back alive. Along the way we collected our favorite things.
Insights into the mystery of color begin with biology. Eighty percent of higher brain activity (originating in the neocortex) has to do with visual input, according to the Eckstuts. How it works: When light waves reach the retina, two kinds of nerve signals are generated. One type of signal is from rods, photoreceptor cells that perceive low levels of light, and the other is from cones, the photoreceptor cells that perceive color. Then the nerve signals make their way via the optic nerve to the optic chiasm, where the signals split in two and move from each eye to the opposite side of the brain. The signals then converge in the thalamus and are sent to the occipital lobe, which serves as the primary visual cortex. The occipital lobe then begins to analyze the signals to make complex associations, such as when "a large blob of red can become a couch."
Photoreceptor cells have evolved to react to certain light wavelengths. Human vision is trichromatic, meaning there are three types of cones that detect color wavelengths -- red, green and blue. Red cones react to longer wavelengths (700 nanometers); blue, shorter (400 nm); and green, in between, (approximately 510 nm). (If RGB sounds familiar, remember that TV and cameras use the same color arrangement.) There are light waves that are undetectable by the human eye -- ultraviolet, for example. Other creatures in the animal kingdom are able to detect UV waves as well as others we humans are blind to, according to the authors. However, we human beings can detect 10 million colors.
What about black and white? White is perceived when all wavelengths of light are reflected back from an object; black, when an object absorbs all light. In other words, the Eckstuts write, white is the presence of all colors; black the absence of them. While cones are most active in daylight, rods come in handy when it gets dark. Rods help us see in the dark as well as assisting with contrast. If there were no rods, there would be no 50 shades of gray.
So far it sounds pretty straightforward, right? Well, it becomes more complicated. The way we perceive light -- from the sun, a fluorescent tube, fire -- is understood as additive color. All of the millions of shades of color are a product of the mixing together of the primary colors. But when light is absorbed by objects, such as the red couch, say the authors, the principle of subtractive color takes over. That is, objects absorb all colors except the color of the object. The red couch absorbs all of the colors of the visible spectrum except for red, which it reflects back to us. While the primary colors of additive color are red, green and blue, the primary colors of subtractive color are cyan, magenta and yellow. The writers do a fabulous job of explaining additive and subtractive colors -- but it took me a a couple of rereads to understand it. (There is more to it when it comes to complementary colors, but I won't go into it here.) Perhaps the most mind-blowing insight here is that all of this is a construction of the brain -- there is no sky blue, ruby red or chartreuse "out there" -- just light waves. As the Eckstuts put it, "All the color that surrounds us is a construction of the brain." I am reminded of the ancient Buddhist koan, "If a tree falls in the forest and no one is present to hear it, does it make a sound?"
The history of color is almost as interesting as the science of it. Plato, the writers tell us, thought there was a causal connection between color vision and tears in the eyes; Goethe tried to order the colors of the spectrum into powerful, gentle and radiant. Sir Isaac Newton posited seven spectral colors corresponding to the music scale: red, orange, yellow, green, blue, indigo and violet. Though modern science has left behind the connection between musical tones and colors, the ROYGBIV acronym is still used to this day, though the selection of these colors was arbitrary; all of the colors are part of a seamless spectrum and violet is not a spectral color but a product of mixing of colors not found next to each other on the spectrum. James Clerk Maxwell, in the latter part of the 19th century, theorized that light consisted of waves that fall on the electromagnetic spectrum, along with UV light, radio waves, X-rays and infrared radiation, among others. Maxwell's insight freed the modern mind from baseless speculation to see color as a construct of the mind that can be measured. The emerging science of color led to understanding why one's ruddy cheeks in sunlight look more sallow in the cool, bluish light of the office. Remember Seinfeld's girlfriend Two Face?
The swatch of fabric, that, under the rug store's fluorescent light, appears to be a perfect match for your couch might not be such a dead ringer in the incandescent light of your living room.
This brings us to the phenomenon of optical illusions. Neuroscientists have discovered that with all of the light wave signals bombarding the neocortex, the brain organizes information as best it can to make sense of it, sometimes making logical leaps in order to avoid overload. This results in our sometimes seeing things that are not there. For example, the Bezold effect (see the image above) happens when we look at a color along side white and black. The color red will appear lighter next to white than it appears next to black. This is illusion is called "simultaneous contrast," which results from the brain approximating contrast when a color is placed next to different colors, say the writers. Chemist Michel Eugene Chevreul discovered in the 19th century that when two highly contrasting colors are put next to each other, the hues "pop," and when colors close to each other on the spectrum are placed next to each other they seem to take on the properties of the other and blend. The discovery fueled the impressionist movement. Georges Seurat's Sunday Afternoon on the Island of La Grande Jatte (1884-1886, see below) exemplifies the principles of simultaneous contrast. Amazing, right?
Not everyone is interested in the biology, physics and chemistry of color. If that's you, then skip to the rest of the book, where each major color is given its own chapter, with stunning photographs and fascinating historical and cultural details. The name for red in many languages is the same for blood, according to the authors. One of the first pigments used by humans in creating primitive art was rust or iron oxide. Ochre -- or hydrated iron oxide -- is a natural earth pigment that ranges from yellow to deep orange and brown. (See the shades of ochre in the Lascaux cave paintings in France from 17,000 BCE below.)
Orange takes its name from the eponymous fruit. In the 13th century the word orange described the bitter taste of the peel, not the color of it. But over time orange came to denote the color, which is said to be the most visible color when placed against a background of blue. The Eckstuts report that orange's visibility is the reason why construction cones, hunting gear and prison garb are all orange. (Orange, by the way, is Markos Moulitsas's favorite color -- the dominant hue of this blog.) The turquoise blue of glaciers (see the Eyjafjallajökull of Iceland below) is a result of absorption of the red end of the light spectrum by densely packed crystals in the ice and reflection of the blue and violet opposite end of the spectrum.
Yellow, according to the authors, has a storied history in China. Beginning with the Yellow Emperor of Huangdi in the 26th century BCE, yellow was thought to be superior to all other colors, being associated with gold. Other cultures, however, have not held yellow in the same regard. Muslims have labelled non-Muslims with yellow stars -- today the Taliban mark Hindus with yellow armbands in Afghanistan. Of course, the Nazis pinned yellow Stars of David on Jews. The theme of color and culture recurs in The Secret Language of Color. Islam has adopted green as its identifying color (see the Green Domes below), symbolizing resurrection and paradise. The color blue, which was all but invisible to the ancient world (except for the sky and sea, of course), adorns Jewish prayer shawls. The color is a reminder to Jews of the sky, the sea and the precious blue sapphire -- all pointing to the Throne of Glory.
Tyrian purple, an ancient dye derived from the gland of a mollusk, was first created by the Phoenicians in 17th century BCE. It takes a mere quarter million of the invertebrates to make one ounce of Tyrian purple, which explains the origin of the words "royal purple" (only the noble could afford it). in Phoenicia. the amount of purple one could wear in ancient days depended on one's ranks. The term "purple prose," coined by the Roman poet Horace, referred to the wearing of purple being overdone by the aristocracy, the authors report. The purple in the quartz mineral amethyst is due to the amount of iron impurities within it. The six-sided crystal reflects light like glass, which is why it so alluring.
The dazzling beauty of color has been marred when used to separate the world into us versus them, the Eckstuts remind us. Melanin -- the pigment that gives color to our skin, eyes and hair -- protects our skin from ultraviolet radiation. Human beings evolved with dark skin closer to the equator (where UV radiation is the strongest). Alas, all of the millennia of racism and bloodshed -- deriving from skin pigmentation due to the sun's deadly rays. . .
I have just scratched the surface of profundity and esthetics found in The Secret Language of Color. The holidays are upon us, and I wager you know someone who would enjoy a book that straddles science, history, nature and politics, all with intoxicating glimpses into the kaleidoscopic wonder of the universe. You will want one for your own library.
Editor's note: This review was originally published at the Daily Kos, which notes that its "content may be used for any purpose without explicit permission unless otherwise specified." The original page can be found here.Like what you read? Subscribe to the SFRB's free daily email notice so you can be up-to-date on our latest articles. Scroll up this page to the sign-up field on your right.