Why do we see white as a color in our brains?

[Philosophy Explorer]

When it's really a mix of colors (we don't see a rainbow, just white). Sort of a supercolor.

PhilX

[Dalek Prime]

Same reason we see a smaller mix of wavelengths as a unique colour, and not as separates.

Our eyes are also imperfect. Watching TV, we can saturate our eyes in blue, and sodium bulbs will seem more yellow, until they adjust, for example.

[Philosophy Explorer]

Same reason we see a smaller mix of wavelengths as a unique colour, and not as separates.

Like yellow and red blend to make orange, e.g. But some colors don't blend, yet all of them do to make white. Any thoughts on this?

PhilX

[Dalek Prime]

Perhaps some wavelengths don't mesh well, whilst others do, maybe. At least to our limited visual sense sense. But the whole mix manages to, overall, come out as the white we see. I'm just surmising, just to mention. I don't claim to know.

[Philosophy Explorer]

Perhaps some wavelengths don't mesh well, whilst others do, maybe. At least to our limited visual sense sense. But the whole mix manages to, overall, come out as the white we see. I'm just surmising, just to mention. I don't claim to know.

It's ok to surmise. An additional fact that may pertain is it's possible to subtract one color from another to get a third color.

Clearly another indication as to how amazing our brains are.

PhilX

[Skip]

For one thing, we don't get our experience of colour from light. We first encounter it in objects - solid surfaces wherein colour appears to be part of the very substance and existence of the objects. We don't learn about light until much later. The colours we normally deal with in life are not of the spectrum but of the colour wheel; not light, but paint. These are the colours we are able to produce, which are much coarser and more limited than the colours made by sun and refracted by the atmosphere, but also much more tangible and accessible.

[Philosophy Explorer]

For one thing, we don't get our experience of colour from light. We first encounter it in objects - solid surfaces wherein colour appears to be part of the very substance and existence of the objects. We don't learn about light until much later. The colours we normally deal with in life are not of the spectrum but of the colour wheel; not light, but paint. These are the colours we are able to produce, which are much coarser and more limited than the colours made by sun and refracted by the atmosphere, but also much more tangible and accessible.

I will reply, sentence by sentence.

It is our brains that give colors their final interpretation. When you say we learn about light much later, what do you mean? Outside of teaching me the names of colors and some blend while others you can subtract to produce more colors, nobody had to teach me about light which is common knowledge. The colors we normally deal with in life are based on objects such as a yellow sun or a red apple that we normally encounter, not a color wheel. The spinning color wheel is commonly used in science class to show that white light is composed of many colors (also a prism breaks it up into a rainbow or spectrum).

So why do our brains interpret white light the way they do?

PhilX

[Skip]

Outside of teaching me the names of colors and some blend while others you can subtract to produce more colors, nobody had to teach me about light which is common knowledge.

You must have been some little prodigy then. I bet a whole lot of adults aren't even privy the common knowledge of refraction and diffraction, or the invisible ends of the spectrum.

When you say we learn about light much later, what do you mean?

Most children have a basic vocabulary of colours by age three. I didn't know light could be broken up into colours, until I was about 5, when somebody explained how a prism works. (That's not necessarily a universal experience: you might not have a chandelier, and you might not ask about the rainbow on the wall, and you might not have a patient uncle; you might have to wait till you go to school.) So I got busy with my water-paint set, trying to mix white. I couldn't do it: all I got was a dirty grey. Why you can't remix paint into white is that pigment is a different thing from wavelength.

When, in early childhood, we are taught the names of colours, what the adults are pointing to is not segments of the light spectrum, but objects that have been painted. We first understand the concept of colour not as broken light, but as man-made pigments. So we store away the understanding of colour as solid, opaque areas, while our early understanding of light is stored away as invisible, untouchable, colourless radiance.

The spinning color wheel is commonly used in science class

I think that's a prism. The colour wheel is used in art class to teach us primary and secondary colours.
In school, when we learn about physics, whether that's a wheel or a prism, we store away new facts about both light and pigment, in yet another compartment of the brain. Perception, received knowledge, language, experience and proclivity all play into what our brain-minds do with the multi-faceted concept of colour. In daily life, we still treat colour, most of the time, in most situations, as pigment applied to objects, and think about it as broken light only in specialized circumstances.

[thedoc]

An object reflects light that is then interpreted as color, if the object reflects all frequencies equally it is perceived as white. Paint pigments are based on absorbing some frequencies and reflecting others, so when you mix pigments you are mixing a material that absorbs several different frequencies of light but not reflecting all of it. White paint reflects all the frequencies and black paint absorbs all the frequencies. The brain interpretes not only the frequencies of light, but also the intensity of the light, giving the 3D image in our mind. Binocular vision and parallax help to fill in the 3D effect of the image in the brain.

[mickthinks]

Because our minds are not configured to see more than one colour in the same place at the same time. So all mixes of wavelengths are seen as single colours.

[Hobbes' Choice]

When it's really a mix of colors (we don't see a rainbow, just white). Sort of a supercolor.

PhilX

There is never an answer to "why". Maybe you should try to answer "how".

Perception and the qualia of perception and incidental consequences of random genetic change, where useful traits are preserved. Conceivably there might be more useful, even objective ways to see "colour", but as evolution is not a intentional or conscious process then it is unlikely to have come up with a perfect answer, since solutions to problems are not sought, but found by differential reproductive success.

You might as well ask why do humans see any colour at all.

[Hobbes' Choice]

Same reason we see a smaller mix of wavelengths as a unique colour, and not as separates.

Like yellow and red blend to make orange, e.g. But some colors don't blend, yet all of them do to make white. Any thoughts on this?

PhilX

Yellow and red do not blend to make orange - that is not in light, only in paint.
Pigment or paint colour wheels are about subtraction, whereas light wheels are all about addition.

http://en.wikipedia.org/wiki/Color_theory

The paradox of this idea is that we cannot see white light, yet we can see white as an opaque "colour".