Is Your Red The Same as My Red?

Hey, Vsauce. Michael here.

This appears blue. This appears yellow. And this appears green. Those of us with normal

color vision can probably agree. But that doesn't change the fact that color is an illusion.

Color, as we know it, does not exist in the outside world, beyond us, like gravity or

protons do. Instead, color is created inside our heads. Our brains convert a certain range

of the electromagnetic spectrum into color. I can measure the wavelength of radiation,

but I can't measure or observe the experience of a color inside your mind.

So, how do I know that when you and me look at a strawberry, and, in my brain, this perception

occurs, which I call "red," that, in your brain, a perception like this doesn't occur,

which you have, of course, also learned to call red. We both call it red. We communicate

effectively and walk away, never knowing just how different each of our internal experiences

really were.

Of course, we already know that not everybody sees color in exactly the same way. One example

would be color blindness. But we can diagnose and discuss these differences because people

with the conditions fail to see things that most of us can.

Conceivably though, there could be ways of seeing that we use that cause colors to look

differently in different people's minds, without altering their performances on any tests we

could come up with.

Of course, if that were the case, wouldn't some people think other colors look better

than others? Or that some colors were more complimentary of others? Well, yeah, but