A colleague of mine presented me with a philosophical question at lunch yesterday. She said that since humans can never experience each others emotions because our experiences are subjective, created by our brains, based on out previous experiences. But this is only partly true. Her example has using as an example that we can never be sure that one persons red is the same as another persons perception of red. Your red might well be the color I perceive as blue, but I might still call it red.
Well here's my take on the problem:
The question is a bit stupid from the start. Colors as we know them are constructed by our minds from the wavelengths of light that is bounced of different surfaces. This means that the same wavelengths hit all of us. This doesn't prove that we experience the same thing though.
In certain fields colors are used to give people a certain emotion, in art, design, marketing, this is a very powerful tool. And it works for all people, with different values given to different colors depending on cultural status.
Now here's the twist:
Color has an evolutionary function. We use color to distinguish what is good and what is bad (green is attractive to all people, as is red, while yellow and black stripes usually mean bad things). This means that our emotional response to color is not random and far from incidental. It is a part of the natural selection that created humankind.
So in my opinion color is really the judgement of our emotional response to a certain wavelength. We don't need to perceive the same red, because we do perceive the same emotion. Color could therefore be added by the mind afterwords. Or in other words: After you see a color the mind gives you feeling to each color, that feeling is your perceived color, and that feeling is measurable to some extent, and known to be alike for most people.
Hard to follow? Am I wrong? Then shoot me down in the comments, I'll respond to all serious comments.