Mix all the paints and you get brown. Mix all the lights and you get white. Why?

Same three colors — red, green, blue. One pile turns into muddy brown, the other into bright white. Let's find the trick… then run the race yourself.

1Two ways to make a color

A color can be given off, or taken away

There are two completely different ways color can happen. Watch each one move:

Light gives off color

A glowing light adds color into the dark. Start with black, shine a color, and now there's color where there was none.

Paint takes color away

A paint is a filter that swallows colors. White light hits it, the paint eats some colors and bounces back only the leftover — that leftover is the color you see.

2So there are two games

Adding glow vs taking away

The adding game

Lights pile glow ON

+ + =

Each light adds its glow on top of the others.

starts dark → gets brighter ↑
The taking game

Paints swallow color

+ + =

Each paint swallows more, leaving less behind.

starts bright → gets darker ↓

3Your turn — stack them yourself

Pick a world, then pile on red, green, and blue

Choose which game you're playing. Then tap to stack each color and watch the spot change. (The light world also has a brightness dial.)

Nothing stacked yet tap a color to add it
Light brightness: full
DARK ROOMBLAZING

4The big race

Same three colors, two finish lines 🏁

Now we stack red + green + blue in both worlds side by side, at the very same time. One spot will end up white. One will end up brown. But which?

Guess before you watch

Remember: lights add glow (starting from black), paints take away (starting from white). You stack red + green + blue in each. Which world ends up WHITE instead of brown?

💡 Stacking lights

…

🎨 Stacking paints

…

5So which game is better?

Neither! Each one trades something

Lights can reach pure white

Because lights only ever ADD, you can pile glow up to brilliant white — or any bright color you want.

The catch: you need a dark room and a power source. In bright daylight the extra glow washes out and you can't "add" your way past the sun.
Paints work anywhere

Paint needs no power and shows up in plain daylight, on paper, on a wall — anywhere light can reflect.

The catch: every layer can only TAKE colors away, so you can never mix your way UP to white — you always slide toward dark brown.

Lights add color and climb toward white. Paints take color away and sink toward brown. Same three colors — two opposite games.

Psst, grown-ups: this is additive (RGB) vs subtractive (pigment) color mixing. Light sources combine additively — overlapping red, green and blue primaries sum to white because all three cone types in your eye get stimulated at once. Pigments mix subtractively: each one absorbs part of the spectrum and reflects the rest, so combining many pigments leaves little reflected light — a dark, desaturated brown (true black is hard because real pigments aren't perfect absorbers). Printers use cyan, magenta and yellow instead of red, green and blue because those are the efficient subtractive primaries.