Colors Explained by a True Expert: Why Do Things Have Color?

Illusion of old wooden door with bright colorful opening surrounded by dark dull colors

Would you believe me if I told you that color is an illusion? It’s true, and I’ll explain why.

People with an artistic eye could spend days talking about the beauty they see in the world around them. Of course, everyone finds beauty in different things. But talk to someone about their personal concept of beauty and color will almost certainly factor in somewhere. It’s easy to see why that’s the case.

When we’re out in nature we’re surrounded by explosions of color that surpass all but the most extensive color wheels. And when we’re indoors we’ll usually find ourselves awash in someone’s aesthetic designs. Even intentional choices to focus on minimalism will usually leverage color in a wide variety of different ways.

Rich treasure troves of color and beauty are even ever-present in seemingly desolate environments. Areas like sand dunes, caves, or subway tunnels only appear monotonous from a superficial glance. When we take a closer look at all of those areas, and similar locations, we can find untold beauty and complexity.

Seemingly plain stone walls usually have patches of color from stains, erosion, fungus, or plants. Sandy plains reveal a treasure trove of color in the form of insects, pebbles, small plants, and even the paradoxical beauty of some litter. For example, we might not like the fact that a natural haven is filled with pieces of broken glass. But when the light hits that glass in the right way it can create a presentation of color that we can’t help but appreciate. And color does tend to be a sort of glue that attaches beauty to almost everything in life.

When we look at the world through the lens of color it’s easy to say it’s inherently beautiful. But there’s just one catch to this worldview. Our entire view of color is essentially an illusion.

Explaining the Nature of Illusion

Rainbow in many colors over field in spring

Most people will instantly argue against the idea that their worldview is based on illusions. However, this is largely due to a misunderstanding of what an illusion really is. Saying something is illusionary doesn’t mean it’s not real. For example, a rainbow is an optical illusion. When we look at a rainbow we see a physical arch made up of differently colored bands. But in reality, a rainbow doesn’t really exist as a physical arch.

The beautiful colors of a rainbow, and its overall form, come about through a combination of light and water. Light sometimes passes through a collection of water droplets in the air. The water droplets act like a prism when light passes through them. The end effect is an illusion of a multi-colored arch. The reality behind the illusion is a mixture of water droplets and light. However, the rainbow does exist. It’s just that there’s a large disconnect between what we perceive and the underlying reality.

Lifting the Veil of Illusion to Rethink Our Idea of Vision

Man pulling curtain aside to a new colorful world

The rainbow highlights a central issue with our view of the world. We instinctively feel that we’re directly perceiving the world around us. Even if we know it’s not the case, we still feel as if our eyes simply act as a window through which our brain is able to perceive our surroundings.

But we’re actually just perceiving light. This is similar to the illusion of a rainbow. Light passes through water and will then appear to be a physical object. In a similar way when we look at a physical object what we’re really seeing is the light reflected off of it. Of course, this isn’t the easiest concept to grasp. Before we can understand our perception of either physical objects or color we need to take a look at our own eyes.

Taking a Moment to Appreciate Our Eyes

3D illustration of human eye structure with descriptions

Our eyes consist of quite a few different components. Light moves through the eye’s cornea, pupil, iris, and lens. Our eyes work with light in a variety of different ways during this process. For example, our pupils dilate or contract in response to lighting conditions. This process will eventually allow light to reach photoreceptor cells in our pupils.

Humans have two different types of photoreceptor cells. We use rod cells for grayscale vision in low-light conditions. And we use cone cells to perceive the world when there’s an adequate amount of light. Our cone cells are further divided by the color they’re able to perceive. We have cone cells to detect blue, green, and red. All of the color we perceive in the world comes about through the stimulation of these cells in conjunction with each other.

The end result of this process is an electrochemical signal which moves through the optic nerve in the back of our eyes. The optic nerve needs to push a lot of data to our brain at an extremely rapid pace. Luckily it’s well suited to the task. The optic nerve is itself a bundle of over a million nerve fibers. Furthermore, there’s a good reason why most lifeforms have their eyes so close to their brain. The shorter the distance between eye and brain the faster we can process the visual data. And there’s a lot of work to be done with the input from our eyes.

Traveling an Electrochemical Road From Eye to Brain

Illustration of human color vision from eyes to brain

We process visual information in different ways depending on context. Think about how quickly you can react when you notice something falling and need to catch it. It often feels like your body moves before you’ve even had a chance to understand what’s going on. This can be due to the fact that information from the optic nerve moves in parallel to different parts of the brain. One part of our brain may process an object’s movement from the optical data and react accordingly before more complex image recognition has had time to take place.

Our occipital lobe, in the brain’s posterior, is the heavy hitter for visual processing. The more advanced executive functions we typically associate with self-reflection primarily occur in the brain’s anterior. While not a perfect representation it’s often valuable to think of the back of our brain as the more primitive areas and the front as the more advanced. So basic visual processing and instinctive action can happen first. Our more advanced artistic sensibilities and narrative interpretation of vision occurs at a point distant from the optic nerve’s main point of contact.

We even have special areas of the brain for some specific types of pattern recognition. For example, think about how you instantly recognize people you know. If they dyed their hair a different color would you suddenly think they were someone else? Of course not, we always recognize each other with even a quick glance. But think about how remarkable that is when something like hair takes up so much of a person’s profile. And similar for clothing choices. We’re able to easily process those differences because we don’t really recognize each other through the more advanced executive function. Instead, our brains are specially set up to recognize faces without needing to consciously think about all of the factors involved with the process.

It’s clear that our eyes and brains put a huge amount of work into creating our view of the world. Think about the fact that this process isn’t a one-time event. Instead, we’re performing this action continually. And the entire process can be done in as little as thirteen milliseconds.

Perception and the World as a Whole

Human world perception concept with planet Earth painted on a woman's face surrounding her blue eye

So far we’ve been able to demonstrate that much of what we think of as vision takes place in our brain. We can expand this further by thinking about how light works. We can think of light as both a wave and a photonic particle. The exact nature of light is itself a tremendously complex subject. But for the moment we can summarize it by simply stating that we can model light as a wave, a particle, or both.

In a sense, we never actually see objects in the world. Instead, what we’re seeing is light reflected off of those objects. This is why we can’t see in total darkness. We never actually look at an object. We instead look at light bouncing off the object. Fully remove all sources of light from the environment and vision ceases.

It’s a difficult concept to wrap our minds around. But we can imagine it as somewhat similar to how a bat uses echolocation to “see” with sound. Likewise, sonar works in a similar way. A bat will create a special type of ultrasound. The sound waves bounce off objects in the bat’s vicinity. The bat can then interpret the resulting noise to create a mental map of the area around itself.

We don’t produce light of course. But our ability to understand our environment through reflected waves is quite similar to the bat’s relationship with ultrasound. We just use light instead of sound to take in our environment.

One interesting part of this process is how different it is from our own self-perception. We think of ourselves actively looking outward to view the world. But in reality, reflected light bounces off objects and into our eyes. The eye then converts that information into electrochemical data to push even further into us through our brains. Our ability to see the world is more a process of it coming to us than the reverse. With this information firmly in mind, we can finally return to the objective world outside of our own consciousness.

Light Can Be Absorbed or Reflected

Illustrating why things have color with light reflection and absorption on umbrella

So far we’ve demonstrated how we can see objects around us. But this doesn’t explain the rich tapestry of colors that we all enjoy and why things have color. Why do we see color in a world we perceive through reflected particles and waves? The answer comes down to the ways in which light can interact with matter before it’s reflected back to our eye.

If a substance is fully reflective then we’ll see the full range of color come back at us. This is how a mirror works. It fully reflects incoming light right back to our eye. If light can pass through an object then it will appear transparent. This is why the clearest glass will be nearly invisible to us. Likewise, it’s why a smudge will appear when we put our finger on the glass. Oils transmitted from our fingertips to the glass will absorb some of the light that would otherwise move through it.

An opaque object will fully absorb part of the light’s visible spectrum while reflecting the rest. It’s this reflected light which triggers the three types of cone cells in our eyes. These cone cells also have a particular range of absorption which works with different frequencies of light. Each type of cone cell reacts to a different part of the visible spectrum of light. This data is mixed into a singular whole after it moves from the optic nerve into our brain. And this is how we finally perceive the reflected light as a color.

Any given material will absorb light differently based on its molecular composition. Think back to the earlier example of oil from our finger appearing on glass. The same general principle applies to all matter. This is why we’re able to change our clothing’s color with dye or a building’s with paint. If the light is absorbed and reflected by one surface before it reaches the underlying substrate then the object will essentially appear as a different color to our eyes.

Not All Light Is the Same

Different light sources with warm, cool, and daylight color temperatures

So far we’ve looked at examples that treat light as a unique and unchangeable constant. But the reality is far more complex than that. We often find ourselves in environments where the light doesn’t encompass the full visible spectrum. For example, you’ll notice that fluorescent bulbs are often labeled as warm, cool or full spectrum.

Warmer bulbs produce more light in the red color spectrum. Cooler bulbs have more light in the blue spectrum. A full spectrum fluorescent light produces the full visible spectrum found in sunlight. And we see similar variation through a wide range of other light sources.

As we move away from sunlight we have different color representations for reflection. This can make something look like a different color when we see it under two different lighting conditions. So don’t blame yourself too much if you think something looks great in the store but quite different when you bring it home. If the store and your home’s lighting differ enough then it might appear objectively different in each environment.

A World of Motion

Colorful digital landscape or sound waves with moving flowing particles

We can now take a moment to consider what all of this means in terms of objective reality. We’ve considered how our eyes and brain construct a picture of the world around us. But what does reality look like if we take those subjective interpretations away?

What we’re really left with is a world of motion. Matter is a complex and continual series of interactions between particles and waves. These entities are continually interacting, absorbing, refracting, and reflecting off each other. Things get even more complex when we consider our other senses. Sound is a process by which waves move through the air to stimulate hairs in our ear’s cochlea. This is then translated to electrochemical data in a similar way to how our optic nerve functions.

Likewise, small bits of matter are constantly floating through the chemical soup we call air. As we breathe in the air our nasal olfactory receptors detect and translate those tiny particles into something we can recognize as smell. We’d be quite right in describing the world as a continual series of interactions between particles. Our perception simply translates this incredible complexity into something we can more easily interact with.

Colors Explained: The Nature of Color and the World Around Us

Big tree with bright green leaves in a surreal black and white landscape

With all of this in mind, we can return once again to the example which started the discussion. Recall that we spoke of rainbows as an optical illusion. At this point, we can see that all of our sensory perceptions could be thought of that way. We talk about color as something inherent to an object. But objects don’t really have an inherent quality that we can define as color. They instead have a specific composition that offers differing levels of light absorption and reflection. Our eyes and brains translate the end effect of that process into color.

This might seem inherently reductionist or even depressing at first. However, that does a disservice to the marvelous complexity involved in our eye and brain’s ability to translate reflected light into a descriptive format we can appreciate. This means that color isn’t an inherent property of matter.

Instead, color as we understand it is a communicative process. Every color we see comes about through direct interaction between an object, light, and ourselves. Our process of visual perception is inherently interactive. There would be no vision in an environment where movement, even at a subatomic level, was impossible. We only see by interacting with our environment through reflected light.

But even this stimulation of photoreceptors in our eyes is only the first step of color perception. Our brains translate those electrochemical signals into thought and subjective perception. Every single moment of our lives is an artistic creation of irreducible complexity.

So the next time you’re struck by the beauty of your environment you should take a moment to contemplate your part in its creation. There’s an old question that posits a tree falling in a forest with no one around. Would the falling tree make a sound? The visual flip side of that question would ask whether the leaves on the tree would be just as beautifully green without anyone to see them. And we can answer that question after looking into how our eyes function.

The leaves wouldn’t be as green simply due to the fact that green only really exists as our subjective interpretation of light reflected at a particular wavelength. Without us it would only be reflected light without an eye to translate that mathematical data into an electrochemical signal. And it wouldn’t be quite the same type of beauty if that signal wasn’t interpreted through the sheer complexity of the human mind and brain.

We essentially paint the world in brilliant color every time we look out upon it. Any beauty we see comes about in large part through our own inherently artistic nature as human beings. We create a new work of art every time we open our eyes.