# What would modern color wheels look like if the human eye saw fewer/different spectral colors?

The typical human eye can see wavelengths between 350nm and 750nm. In 1666, Isaac Newton used a triangular prism to split a beam of white into a rainbow and then define the first color wheel.

Fast-forward to modern times, most color wheels we find in graphics editor software look something similar to this:

Now, in another universe, Iseec Nawton did the same experiment. However, he did not see a rainbow of Red, Orange, Yellow, Green, Blue, Indigo, and Violet. Instead, He saw a rainbow of Red, Orange, Blue, and Green (in that order).

Ignoring any evolutionary reasons for this to happen, how would their modern color wheels look?

Edit: For clarity, I'm considering that Iseec Nawton saw fewer colors. If the change in order makes this question impossible to answer, I'm okay with changing it to Red, Orange, Blue, and Green.

• You either are talking about changing the properties of light/glass in a way that the prism splits the light in a way defies our understanding, or you're talking about 1) seeing fewer colours. and 2) their names being swapped around from ours. Be aware that the colour wheel is different from the spectrum you'd get in a rainbow or from a prism - so there's a tangle of that to be cleared up in your question. Could you clarify? Sep 9 at 22:56
• There is no relationship between how a color wheel looks and how many basic color terms there are in a language. For example, many languages have a single basic color term for what English distinguishes as green and blue; and English has a single basic color term for what Russian distinguishes as siniy and goluboy. So the fictional Newton spoke a language where the fictional word blue means grue and the word green means violet. (Fun: in Newton's English, blue was what we call turquoise, and indigo was what we call blue.) Sep 9 at 23:09
• If the color wheel is being used as a color picker, you would have 4 colors to choose from, but I think you would swap the blue and green sectors to have them ordered more logically. What that color would be, would be determined by what looks good to the person creating the color wheel. Or more mathematically you could try to use a formula for what the Average Red, Orange, Green, Blue colors are. The Wikipedia Article shows a variety of color wheels en.wikipedia.org/wiki/Color_wheel as possible examples Sep 9 at 23:23
• -1: (a) You've tagged the question science-based, which means the normal spectrum of light is in play. That means the only answer to (part of) your question is that humanity chose to reverse the meanings of the words "blue" and "green." (b) Changing how humans perceive color only changes what they can see along the spectrum. We can see a wider or a narrow spectrum, we could be more or less perceptive about the spectrum. But that's it. science-based severely limits your answers.
– JBH
Sep 10 at 4:15
• I did have some trouble when deciding on the tags for this question. I added the science-based because I start the question with a comparison to the real world. After I read the comments, I chose to remove the tag. The question has been edited for extra clarity.
– GFA
Sep 10 at 11:35

## 2 Answers

Your Colour Wheel Looks Like This.

• This could use some explanation, but it does technically answer the question
– Atog
Sep 10 at 16:35
• This is almost exactly what the milk left over from a bowl of Fruit Loops looks like.
– Tom
Sep 10 at 19:49

Newton didn't dispassionately identify seven colors in the wheel in the manner of a good scientist. He divided the wheel into seven parts because he believed (wrongly) that there was a connection between colors and the heptatonic musical scale. Two of the color wedges are half as wide as the other five because the heptatonic scale has five whole steps and two half steps.

Here are some reasonably accurate images of a spectrum:

(They are against a gray background because it's impossible to represent spectral colors in sRGB without mixing them with white. You should mentally subtract out the background.)

Judging by these images, if Newton had been mystically predisposed to see four colors in the spectrum, they plausibly could have been red, orange, green, blue (in that order). In that case, modern color wheels would be no different, since they aren't based on Newton's musical model.

If he'd wanted to see seven colors in Daron's color wheel, he could have done that too. (I see red, orange, violet, indigo, blue, green, brown.)

It's hard to know how to interpret the switching of green and blue. It could just mean that the English words are different and everything else is the same. It could mean that the green and blue qualia are swapped, but it's hard to know what that means since we don't understand qualia. We don't even know that different people are experiencing the same qualia when they say that they see green or blue.

• "We don't even know that different people are experiencing the same qualia" -- I've heard we have good reason to suspect that we do. One example I remember is an experiment that relied on contrast and brightness under dark viewing conditions, which purported to prove that "orange" and "blue" are the same for all people (with healthy vision). Wish I had a link, but I learned it in a philosophy class 1000 years ago.
– Tom
Sep 10 at 19:52