Only a small portion of the electromagnetic spectrum is visible to us. Sir Isaac Newton broke the visible portion down even further as an attempt to describe all the possible colors that we see. In third grade we learn that the visible spectrum can be remembered using Roy G. Biv–which must be the strangest mnemonic device ever created–and includes red, orange, yellow, green, blue, indigo, and violet. Black is the absence of light, white is the presence of all colors in the color spectrum. There are a couple shortcomings in thinking about color in this way.
First, who really knows what indigo is? Some have claimed that Newton organized and labeled his color spectrum to include seven colors, the holiest of numbers, in order to avoid criticism from the church. That seems likely, given that indigo seems to occupy only a small part of the gradient compared with other hues. Thus, many now list the visible spectrum as Roy G Bv. But what about cyan? And what about that bright looking color
Magenta and cyan make up half of the four inks (cyan, magenta, yellow and black) used to print almost all of the printed material in the world. Furthermore, cyan and magenta are prominently represented in the additive color system that powers the computer or phone screen you are currently reading. But magenta is nowhere to be found on the traditional grade school color wheels. And what about Newton’s color spectrum? Where can we place magenta on the map?
As it turns out, Magenta cannot be located on the spectrum because it does not exist on the visible spectrum. Magenta does appear in nature of course, in flowers and between the two parts of a double rainbow. But to understand why it is perceived so brightly but not in the spectrum, we need only to look to our physiology.
We have three kinds of cones in our eyes–receptors configured to receive red, green, or blue-violet light. Ever wonder magenta and cyan are so difficult to look at for long periods of time? Magenta, cyan and yellow appear so bright to our eyes not because they contain more light, but because to perceive those colors two sets of cones are firing at once! Magenta is not a color exactly, it’s two colors–red and blue-violet at once–with a complete absence of green. Got it? One more time–magenta is only perceived psychologically when pure red and blue light mix, and green is completely absent.
Of course, all colors are perceived physiologically and not necessarily “seen”–as color blindness and the extreme differences in color perception between humans and between humans and other species reveal. If a viceroy butterfly sees millions of colors and a golden retriever sees very few, how can color be anything but a physiological phenomena? But magenta is a special case in that it is the only color which may only be perceived as a combination of two other hues.
Color harmony is generally understood as pleasing relationships between two or more colors. But put more scientifically, magenta is already and always a harmony, more akin to the way harmony works music–the perception of multiple wavelengths at once!