An unknown number of women may perceive millions of colors invisible to the rest of us. One British scientist is trying to track them down and understand their extraordinary power of sight.An average human, utterly unremarkable in every way, can perceive a million different colors. Vermilion, puce, cerulean, periwinkle, chartreuse—we have thousands of words for them, but mere language can never capture our extraordinary range of hues. Our powers of color vision derive from cells in our eyes called cones, three types in all, each triggered by different wavelengths of light. Every moment our eyes are open, those three flavors of cone fire off messages to the brain. The brain then combines the signals to produce the sensation we call color.
Vision is complex, but the calculus of color is strangely simple: Each cone confers the ability to distinguish around a hundred shades, so the total number of combinations is at least 1003, or a million. Take one cone away—go from being what scientists call a trichromat to a dichromat—and the number of possible combinations drops a factor of 100, to 10,000. Almost all other mammals, including dogs and New World monkeys, are dichromats. The richness of the world we see is rivaled only by that of birds and some insects, which also perceive the ultraviolet part of the spectrum.
Researchers suspect, though, that some people see even more. Living among us are people with four cones, who might experience a range of colors invisible to the rest. It’s possible these so-called tetrachromats see a hundred million colors, with each familiar hue fracturing into a hundred more subtle shades for which there are no names, no paint swatches. And because perceiving color is a personal experience, they would have no way of knowing they see far beyond what we consider the limits of human vision.
Like disgust or delight, beauty is a visceral emotion, a pleasure that Nabokov described as being synonymous with “the the sudden erection of your small dorsal hairs.” That beauty can be localized to the mOFC only reminds us that it’s part of the pleasure spectrum, since that brain area has consistently been implicated in the recognition of delightful things, from the taste of an expensive wine to the luxurious touch of cashmere.
But why does beauty exist? What’s the point of marveling at a Rembrandt self portrait or a Bach fugue? To paraphrase Auden, beauty makes nothing happen. Unlike our more primal indulgences, the pleasure of perceiving beauty doesn’t ensure that we consume calories or procreate. Rather, the only thing beauty guarantees is that we’ll stare for too long at some lovely looking thing. Museums are not exactly adaptive.
Here’s my (extremely speculative) theory: Beauty is a particularly potent and intense form of curiosity. It’s a learning signal urging us to keep on paying attention, an emotional reminder that there’s something here worth figuring out. Art hijacks this ancient instinct: If we’re looking at a Rothko, that twinge of beauty in the mOFC is telling us that this painting isn’t just a blob of color; if we’re listening to a Beethoven symphony, the feeling of beauty keeps us fixated on the notes, trying to find the underlying pattern; if we’re reading a poem, a particularly beautiful line slows down our reading, so that we might pause and figure out what the line actually means. Put another way, beauty is a motivational force that helps modulate conscious awareness. The problem beauty solves is the problem of trying to figure out which sensations are worth making sense of and which ones can be easily ignored.