What is art? Art is the language we use to say that which cannot otherwise be said. Art is gestalt; it is where 2 + 2 equals anything but 4. It is alchemy, the combining of seemingly disparate elements to create a whole greater than the sum of its parts. It is a deep appreciation of the situation where there is no right answer and there are as many answers as there are questions asked. Art is asking questions, of others, of our selves.
What is color? Color is not a thing. It is the visible portion of the spectral band. We are attuned to this radiant energy to help us navigate the physical world we call this thing color.
Color is irregular and a-systemic. It refuses to be quantified absolutely in any meaningful, useful way. What is true for the physicist is not so for the artist, or for that matter, the honey bee. The linguist, the botanist, the anthropologist, and the interior decorator all require color to conform to different means and protocols. Even the web designer must manipulate color differently from the auto-body detailer. It is a slippery thing, color. And on top of all this, try taking your color terms to different countries, cultures and languages. Color is distinctly not universal.
Color has successfully frustrated some of the greatest thinkers, painters, poets and scientists for millennia. 40,000 years ago human beings smeared oils, fats, soot, earth and blood on the walls of their living quarters, they decorated their homes with images of animals, hunters and their own hands. They chose one colorant over another to designate this or that, and in so doing played with color theory. We wrestle with essentially the same questions when shopping for clothes or picking paint swatches for our bathrooms. As has been said, the more things change the more they remain the same.
If color is mutable, irreverent, and rudely beautiful so is art. If art is generous, challenging, visceral, sentient and real, so is color.