Your brain is like an organic computer. At it’s core, our brain and computers have ways of receiving information, then processing and showing an interpretation of that that info. Light and it’s colors to us is like 1’s and 0’s to a computation system.
Light carries information. In a recent TEDTalk there was a speaker that demonstrated a new type of wifi internet that works through light. The internet worked under light (which was hooked to wifi somehow), but in a shadow, stopped. Likewise, light tells humans various things. It can tell ‘color’, composition, distance, temperature, whether the object it is illuminating is coming or going and many other things. Yet some light we are unable to see. Infrared is everywhere yet can’t be seen. In rainbows even. Beyond the red stripe (in a rainbow) there is another stripe we can’t see. This is infrared. Some animals can see it, some can’t. It depends on their evolution and environment. A Mantis Shrimp can see visible light (what we call the light humans can see) along with body heat at the same time.
I could go on forever, but I won’t. Basically we see colors because an object is made of various elements that invite certain wavelengths of light (each color is a different wavelength) and absorb them while reflecting others. We see purple when an object absorbs red light and reflects blue (or vice versa). The object is not really purple, the light reflecting off it is (but only in our brain’s perception). Different species see identical colors in different ways (meaning as a different shade or color).
I could go into other things, like dark matter. We know it’s there because of the gravity it creates, yet we cannot see it because it neither absorbs or reflects light. It’s there but invisible. No color exists if light cannot interact with the object, but that does not mean it doesn’t exist. It is sort of like the saying “if a tree falls in a forest with no one there, does it make a sound?” The answer is yes. Seeing and hearing are side effects of evolution and survival and that works well in most places.
Some say seeing is believing, but anyone willing to use the intelligence we have developed know this is very far from true.
So there.. color is an illusion. Essentially color IS light. Color is the light reflected and absorbed and not the actual object itself. It’s just that different elements want some colors but dismiss others. We can luckily know this without really seeing it.
I will end this by explaining the picture posted with this entry. It has blue and yellow bars with four squares of different colors. Look at it from a distance and it appears that the boxes on or behind the yellow/blue bars are four different colors. Get close and look at each one individually. Cover the blue and yellow bars if need be, but you will realize that the top two boxes are actually the same color of red, while the bottom two are the same green. It can be hard to see because while you know they are identical colors, your brain perceives it as otherwise. Yet you KNOW they are the same. So you trick your brain into seeing it correctly by looking close and possibly having to cover the yellow and blue bars.
This proves the brain fills in blanks when it is mixing or missing information. Hence, color is an illusion and we don’t see colors as they truly are. They really don’t have any color at all. We are only seeing (and interpreting) the different wavelengths of light. Light does not show us colors. Light, itself, is color.
It’s great humans are smart enough to know that what they see is not always reality. Well, some.