magenta

We take for granted that things are as they seem “out there” in the world. But when we get to the color magenta, we realize our brains are just making things up.

There are two ways we humans figure out the world around us: our observations and our experiences.

In the first way, with our observations, we are able to determine the structure of the material world “out there” by taking inventory of all the quantifiable stuff around us: how much things weigh, how big they are and what they are made of, how fast they are going and where they are going to. With these observations we learn something about structure and mass and the probable outcome of a thing, and in so doing we come up with a truth about that thing. The aggregate of all these “things” we observe and measure is the real, physical, material world. This is an empirical approach.

The second way is a phenomenological approach — using the brain that figured out the weight and mass of a thing, we now see that the thing in our hands has a “color.” Let’s say what we have is this pinkish color:

From an empirical standpoint, we know this pinkish-colored thing in our hands has weight and substance, so we are able to infer that it’s made up of atoms. But the atoms that give the thing in our hands its weight and mass are not pink. The atoms do not emit “pinkness.”^[1] We see pink, but its color is not part of our quantifiable material world — color is part our phenomenological experience of the world.

what is color?

Visual “colors,” as we experience them, are not physical objects on a rainbow per se. Colors are symbols created in our minds as the brain interprets the wavelengths perceived by the photoreceptor cells of the eye. The visible part of the frequencies of wavelengths are detected “out there” in the world and processed by the brain and “mixed” in our mind so that we experience color.

Color is an interpretation. That’s where we get the old question, do other people experience the color red as the color that I see when I see red?

Setting aside that question for a moment, let’s return to the physics of color, because we rely on physics to tell us how the world works. Colors, as we perceive them, are interpreted by our brain from two sources: as color perceived in the frequency of reflective light and color perceived in transmissive light.

Reflective light refers to the aggregate of wavelengths that first bounce off an object before getting to your eye, like the color green of a leaf on a sunny day. Transmissive light, on the other hand, is the wavelength of electromagnetic energy emitted by the source light itself, like the light from the sun before it hits the leaf.

Reflective light is what happens when the particles of an object (the leaf) absorb some of the wavelengths of the sunlight by the molecular structure of the chlorophyll, but there are unabsorbed wavelengths of light, too, that are reflected off the leaf. And this unabsorbed, reflected light contains the frequencies of the visible color green that reaches your eye.

By contrast, with transmissive light, the source light itself emerges from the black nothingness and combines color frequencies in proportion to the aggregate of the resulting color. This is happening right now as you read this computer screen. The brain interprets the frequency of the electromagnetic energy in front of you and assigns colors associated with those wavelengths. The projected light of the screen is received directly in the eye and mixed in the brain without having bounced off anything.

But with all this frequency and wavelength and perceiving, is it actually color that you see?

No, the wavelength or frequency of light itself is not color. Even the visible spectrum, the mind assigns a symbol to represent the wavelength your brain takes in. That symbol is interpreted as color. The wavelengths received in the retina are interpreted by the brain, and the brain “shows you” color. But the brain does not show you all the frequencies and wavelengths, like those of infrared and ultraviolet, only the so-called visible spectrum. The other frequencies on the far end of the rainbow are there, as we detect through our empirical methods, but we do not experience them.^[2] And that seems to be the structure of our world — much of what we experience as we go through our day is not the material world itself but rather our phenomenological experience of it. It’s not weight and mass and trajectory that play out in our mind, it’s the color and taste and smell. Much of what we experience through our day is actually — literally — all in our heads.

the nonexistence of magenta

Which brings us to the color magenta. When the mind does not have a symbol to associate with the particular wavelength, it just makes one up. Magenta is not a really color. It is an extra-spectral substitute for a wavelength that the mind thinks should be there, but that does not actually exist in the visible light spectrum. It is not on the rainbow. It’s the brain’s attempt to complete a pattern, to close a circle, to connect red on one end of the visible spectrum with violet on the other. It’s a phenomenological construct, created entirely in the mind, which helpfully puts something “out there” that is not there.^[3]

Here is our pinkish thing again. Only this time, we will call the color that we see magenta.

OK, then, where is it in the spectrum?

what magenta tells us about the world

Not every animal around us can see color. So why do we, as humans, see the world in particular colors instead of just black and white? What survival purpose in humans does the ability to see color provide? And what is its evolutionary value? We could say color is what you get when you have an advanced brain, but if color — assigning a mental symbol to a wavelength — is a characteristic of an advanced brain, then why can’t we perceive ultraviolet wavelengths, like bees do?^[4]

Which brings us to the question again: do other people experience the color red as the color that I see when I see red? More importantly, if that bee with a different “eye” structure than me (who has a different brain and different senses and different experience than me) is experiencing the green plants in my yard drastically differently than me, and who is getting by just fine with her 5,000 ommatidia instead of eyes,^[5] if we are both “looking” at the same green leaf on the same flower, but we see something completely different, are we both sensing the same reality? Is our interpretation of what’s really “out there” only at best a helpful heuristic created by our mind that allows to us navigate the material world  as if we are experiencing what we experience? Or, in actuality, is what we experience only a useful metaphor — that what we experience throughout the day is actually the interpretation of a bunch of symbols, impressions and artifacts of pattern recognition?

The bee has her reality, and we have ours, and nature lets both of us go on and survive and reproduce, and nature seems pretty agnostic as to which metaphor is superior: the bee’s phenomenological experience of its structural reality, or the human’s structural reality. But which one of us is “right?” What is the true reality of that flower? Are we both right, or are we both actually wrong?

Plato’s Allegory of the Cave is useful here.^[6] Prisoners are chained to the floor of a cave and face a wall from which they cannot turn (the phenomenological experience of living inside a brain). Their heads are bound, preventing them to look at anything but the wall in front of them (the structure of the material world). On the wall the prisoners see shadows from a fire behind them. The prisoners do not see the fire, so they cannot understand what fire is, nor do they know that the wall is illuminated by it. Just that on the wall are shadows and shapes they see. They cannot know that these shapes are cast by puppeteers in front of the fire who, from behind the prisoners, create everything the prisoners see on the wall. But on the wall in front of the them the prisoners live out their lives in the reality of the cave. The only thing the prisoners actually know is what can be subjectively perceived in front of them: the shadows on the wall. The shadows are their world, and their world is shadows.

The allegory continues, and over time prisoners become clever at identifying the shapes on the wall and giving them names (“that one is a tree,” “that one is dog”). Some become skilled at predicting patterns that occur — “a dog approaching from the left is always preceded by a cat” — and congratulate themselves when they make accurate predictions based on their observations (such as we do with our current science). The prisoners exude confidence — even hubris — with their knowledge, of their grasp of their world, living on the edge of history in an enlightened age. But, in actuality, what they perceive as a dog, is not an actual dog. It is not even the shadow of an actual dog. It is the making of the puppeteer (in our brain), which creates a world of shadows. It is not until Plato frees one of the prisoners and takes him outside the cave — into the light the prisoner has never known — does the prisoner see the world for the first time, as it truly is.^[7]

But can we do that? Can we get outside our brain, of our own subjective experience?

Subsequent philosophers, such as Descartes and Kant, conclude that we cannot have a purely direct experience of reality. Our experience of a thing is not the ding an sich, the thing-in-itself.^[8] What we experience in our mind, what we call reality, is only the result of appearances whose existence occur only in representations. Actuality may be perceivable, but ultimately it is not unknowable. We are stuck looking at shadows.

Science, too, has begrudgingly come to a similar take. While Einstein’s relativity theory and, later, the field of quantum mechanics assure us that there can be an empirical objective reality “out there” (that the world we perceive is not created entirely in our solipsistic mind), the world is most likely a far different reality from what we actually experience. In special relativity, there is a separate space-time for any given observer in its relation (its relativity) to the other observer.^[9] And in quantum mechanics, the world “out there” is made not of empirical certainties, but only probabilities from which we collapse one perspective, one interpretation from a multiplicity of possible and partial viewpoints.^[10]

of magenta, of bee-ing and of time

The experience with magenta is just one of the many illusory phenomena created by the human mind.^[11] Taken in aggregate, we are left with an important question: does our brain’s ability to hallucinate these illusory phenomena — to “see” the color magenta when it’s not really there — give us the confidence that we actually know what’s going on “out there,” that we can ever see the world as-is rather than merely as-if?

Really old notions like Plato’s Allegory of the Cave and really new ideas like quantum physics seem to be not so far off from each other. ^[12] We just keep discovering new ways of coming to the same conclusion. But the fact that the color magenta even “exists” suggests that — though we have come far — we should be very careful in congratulating ourselves too much.^[13] Because even if our scientific age can bring us cell phones powered by quantum mechanics and aeronautics that take us to the moon, we are chained to the floor of our brain. We may only be good at making very accurate observations of the shadows on the wall.

Posted May 30, 2022
Last updated October 29, 2023