Blue is the color that culturally people develop last.
This is weird. Colors are colors, and we all have them, don’t we?
No, we don’t.
Languages develop words for black and white first. Then red. Then yellow or green. Blue is the last one.
In fact, there are many languages that have no word for blue at all, like Japanese, Korean and Thai. Homer’s Odyssey and Iliad contain dozens of descriptions of colors, and not a single one of blue.
Here’s a Radiolab talk about colors.
It’s an anecdote, but one researcher told his toddler all about colors including blue. But he didn’t tell his toddler the sky is blue. When she was a little older, and she was asked what color the sky was, she had no concept that it was a color. Odd.
Another thought: blue is the rarest of the major colors in nature. As George Carlin noted, there is no blue food. There aren’t many blue flowers either. Or animals. Or stones. There aren’t many body parts either, besides blue eyes, and those were geographically rare until the Germans invaded western Europe.
Another idea: blue is the hardest color to create artificially. Prussian blue was invented early in the 18th century. There are natural dies, but not many of them. Recall how important the production of indigo was to the Carolinas in the colonial period. You could also use woad. Both are almost purple when fresh but fade through blue to green with time. And, the plants actually produce the same chemical, so it isn’t like you’re getting a different color. You could also crush the semi-precious lapis lazuli into a powder called ultramarine. Again, remember how important lapis was in ancient history, and yet today few of us would know the stone if we saw it.
And here’s one more bit of trivia. The ancient Egyptians knew how to make a blue dye from minerals almost 5K years ago. And they had a word for the color blue. Today, we know the chemical composition of that blue, but not how they actually did it.
P.S. There is an old but related post on vX that I could not find. This was about the colors we have in common.
FWIW: I get complaints about the color scheme of this blog. I get few compliments. Back in the 90’s there was actually a push for yellow on blue as a standard. Black on white is harder on the eyes when coming through a screen (gee, you’ve probably noticed that at the end of the day). The reason for yellow on blue was that these are colors that color-blind people can most easily distinguish. And no … I’m not color blind.