Black is apparently the lack of any light (color).
If you have black, and add white (all colors), why does it turn grey instead of white? If you have no color and add every color, wouldn’t you end up with every color (white)?
How does that work?
Gray is dark white.
But if you add all colors to no color, wouldn’t you have all colors? That’s like saying 0+6 =/= 6.
Gray is “all colors”. Just not very bright.
Actually, gray is a pale black.
The better answer is, kidding aside, that all colors being present doesn’t so much produce white as a neutral hue. White is a bright neutral hue, gray is a medium neutral hue, and black is a dark neutral hue.
Color ≠ Intensity.
Are you talking light or pigment?
Light: Black = no color, white = all colors. black + white = white.
Pigment: Black= all colors, white = no color. black + white = grey (all colors, less intensity)
Oh, I see.
Mind-fucked…
Think about what you are seeing. It is light being reflected from a source, so black is what you get when no light is being reflected, and white is what you get when all light, the whole spectrum, is reflected.
I had a red and white pinstriped shirt on which the stripes were obvious up close. At a distance, the shirt looked pink. Magnify a gray substance and you’ll find a mixture of black and white regions- not gray ones.
It’s Additive Color vs. Subtractive Color.
Does that mean that there is no actual “gray” color then? Just assimilated regions of black and white that our eyes interpret as a shade at certain magnifications?
Maybe 
You could find that, but you won’t necessarily find that.
Pretty much, yeah, at least when it comes to pigments in paint. Most pre-made grey paint is pre-mixed black and white pigments. Black, grey and white are all the same “color” in they reflect and absorb light evenly across the color spectrum, just reflecting different amounts of light.
Blue paint, for example, looks blue because it absorbs the other colors and reflects blue (plus a bit of green and violet, too).
It doesn’t matter whether it is additive or subtractive. Whether you use lights or pigments, gray is dark white or light black, i.e. your eye is receiving more light than something black and less than something white in the same field of view.
Black, white, and gray are relative terms. Consider that a black sunspot is as bright as a direct view of the filament of a lightbulb, but dimmer than most of the solar surface. Similarly, the white paper of a book is dimmer indoors than the period at the end of the sentence viewed outdoors.
It’s also worth noting that dark yellow is brown. Same color, just not as bright. It is all about the contrast.
My favorite illustration is a projection screen, like you might find in a classroom or conference room. They’re usually white with a black border. Except the “white” is actually the darkest black you’ll ever see in a movie projected on that screen.
That said, for pigments, there really is such a thing as absolute white and absolute black. A true white surface will reflect 100% of the light incident on it, and a true black surface will absorb 100% of the light incident on it.
True enough. I don’t have to explain this to you, Chronos, but others might be surprised at how low a reflectance will still look white under the right circumstances. For example, the moon at night is a vivid white, even though it reflects a mere 12% of the sunlight, only a few times more than asphalt.