Most color theory and color wheel info is about mixing colors and working with contrast. But there are more color effects in painting, that can't be explained by mixing or contrast. Goethean color theory is based on the effects of light and darkness. These are immaterial, yet visible qualities. From various physical tests (with a prisma or by analyzing the atmosphere), you can say: reds are about active darkness, in a passive light. And blues are about active light, carried by a passive darkness. I'm an artist, a painter. In the beginning, I didn't use color. Still, I noticed that a white painted on black gets a different look than a black painted on white. When you paint a semi-transparant white over black, it gets a cold, bluish tone. And when you paint a semi-transparent black over white, it gets a warm, brownish tone. Years later I found, that this phenomenon can be explained by Goethes theory of color. Goethes doesn't juggle with wavelengths, atoms or breaking indexes - instead he consciously uses only his own perception. He found that color appears (in for example the atmosphere), when there is some light, some darkness, and some transparancy (better said: a transparant form of matter (like air, water, glass etc.). Warm colors (yellow-orange-red) appear when you see darkness before light, and you see blues when, seen from your standpoint, you see light before darkness. In a prisma, it works about the same way. Check the links on the bottom of this page, for more on that. Of course, atoms and wavelengths have a truth of their own. But it's a machine-truth. We don't see atoms or wavelengths. Newtons theory of color is good for building color-tv's, but for art it was a disaster. More than once, I heard my colleague-painters declare color actually doesn't exist, and is a purely subjective phenomenon. That's not something an artist can work with. With Goethes theory of color you can't build color tv's, because it describes the ideal part of nature itself. But Goethes theory of color is great for artists. I took some lessons of watercolor-specialists, who in their turn had lessons of a unique watercolorist (Liane Collot-d'Herbois) . She took Goethes knowledge as a basis for color-studies, in which she explored the features of each color in the way it appears between light and darkness. She also found out, that colors don't have to mix as matter at all. She could bring out a radiant magenta, by using only blue and yellow paint. The magenta was there for everyone to see. Even if it was only light, it appeared as if actually painted on. And we all know, you don't get magenta, when you mix yellow and blue paint - you get green, when you mix yellow and blue. After my watercolor-lessons, I took this knowledge into oil painting and found it works exactly the same way in oil painting. But more important: I noticed that the color effects I learned happen exactly the same way in mechanical and digital color reproduction. The interval color that was created in a painting, comes out stronger on a photograph of the painting, or on an LCD screen or a color copier. In color photography and graphic design these color effects play a role too. Professionals learn to more or less deal with them, but they are never really explained. When you do digital photography, and work you your pictures on the screen, you'll probably know that inexplicable magenta hue, coming from nowhere. When you make a picture in black and white, and have very well-balanced tonal values (light and darkness), stripes of green and magenta appear. When they touch, you get blue. This also happens, when you color-copy a black and white picture, with the lid open. The funny thing is: before I found this out, I learned from two highly spiritual watercolorist, that magenta and green can make a light blue interval color… The effect of the interval is not only about color mixing as light. It has to do with the effect of darkness or shadow as well. For the effect to appear, colors must be equally strong, they must be painted atmospherically, and there must be a little space in between, where both don't 'come'. The yellow interval between green and red can be explained by color mixing as light, but the magenta interval between yellow and blue can't. The darkness is playing a role there too. I have spoken about it with a goethean science teacher, he doesn't understand it yet either. But I'm sure it will be understood some day. There is still a lot to explore, when it comes to color effects. This is really a kind of science, and we all know science is a very slow process. But at least now I know, why reds look great when painted on white semi-transparant, and blues look ugly when you paint them that way.