- Why is the sky blue? It's one of the most common questions asked by both kids and adults, unless you're from ancient Greece. I know, I know, you'd think the country that is now ubiquitously known
for beautiful blue rooftops, crystal blue waters, and a blue flag would have a longer
history with the color. But if you were to read Homer, uh, not that one, the famous ancient Greek writer
from the 8th century B.C., you'd notice that the word
blue isn't mentioned once. Through thousands of pages of
"The Iliad" and "The Odyssey," black is mentioned 170 times,
white 100, red 13 times, yellow and green each around
10, but blue never appears. What's weirder is that
Homer describes things that we would normally
call blue, like the ocean, as wine-dark. He even calls honey
green and sheep violet. For a while, some suggested that maybe the ancient Greeks just saw
colors different than we do, or maybe they were all color blind. But we now know that
color vision developed around 30 million years
ago so that's not it. It gets even crazier. As historians and researchers
began looking into other ancient civilizations,
they realized the same thing. Almost none of them used the word blue. From Icelandic texts
to ancient Indian epics dating to about four millennia ago, to ancient Chinese writings, and even the original Hebrew Bible, all of them fail to mention blue once, while all of them mention
black, white, and red, and many, the Bible included,
also mention green and yellow. Again, it's not like they
don't talk about things that we would call blue. They describe the ocean
as wide, stormy, silent, but never blue. It wasn't until the mid-1800s that linguists began to analyze
the history of languages and found something peculiar. In every culture, black
and white are first. Then the first color to enter
the language is always red. Then yellow follows, then green. And then blue is the final
color to enter language in every single culture. Over the years, researchers have found some minor exceptions
with the middle order, so green and yellow, but red is always first
and blue is always last in every single language. So, why this order? There's two main theories. First, the evolutionary
explanation is simple. Black and white help distinguish
between night and day, light and dark, and are
the most clear and useful, so every culture has those. Then red, it's often associated
with blood or danger. Even human faces and communication use red through the galvanic skin response, like when you blush or are stressed. Green and yellow entered language
as the need to distinguish between ripe and unripe foods. And blue? There's very few blue things
that we actually interact with. Blue fruits are pretty rare. Blue animals are rare too. And when they are blue,
it's often not a pigment, but a sort of light illusion,
like in butterflies. Even the modern European
language words for blue are derived from ancient
words for black or green. The second explanation suggests that these words don't enter language until humans could make them. Red being the easiest and
most accessible color, because you just take a piece of dry clay and use it as a crayon. If you think of cave, for example, there's a lot of black and red in them. But blue? It's one of the hardest colors to create. For thousands because of years, nobody had it except the Egyptians, and they had a word for it. So does this mean that
ancient people couldn't see those colors before
they had a word for it? Not exactly. Early humans would have considered colors as simply hues of black, white, or red, which sounds kind of crazy, but there's actually modern
day evidence for this. If you look at these 12 colors, can you spot the one that's different? We might think clearly it's this one, but when presented with a similar chart, the Himba people of Namibia, who don't have a separate word for blue, take longer to point out this distinction. On the contrary, when
looking at green colors, they are more quickly able
to note the difference that we wouldn't catch
as quickly, this one. And this is because they have
more words for types of green than we do in English. In fact, one of their
color categories clumps some types of blue and green together, while they have other color categories for different greens still. In the 1890s, anthropologists discovered that indigenous islanders in
New Guinea described the sky as black or dirty like water. Which, if you think about
it, isn't that surprising. Even if you look at a
color picker in Photoshop, it's clear that a dark or
navy blue isn't actually that far from being black, and is quite far from other hues which we would still call blue. In that sense, black would
have been a much broader term for early and ancient humans. It's kinda like how these
are all shades of red. We wouldn't call them
different colors necessarily. But this, in English, we call pink. Even though it's technically
just another shade of red, we've decided to categorize it as separate and as a result, it's
different in our minds. Of course, even if we didn't name it pink, we'd still be able to see
that it's a different color, a lighter hue, but ultimately, we'd
consider it a form of red. Now, you might be thinking
this just seems semantic. So what, they have different names. There's no functional difference in the actual color we're seeing. But neuroscience has
found that to be untrue. It turns out, and this is mind blowing, that language trains our brain
to see colors differently. What this means is once we
have a new word for a color, there's a feedback loop in the brain and this exaggerates the
differences between those colors, especially at the border
areas between them. We get used to calling these
colors as distinct hues and as a result, the
brain more aptly sees them as distinct hues. Without the word, you
would still see the color, but you wouldn't notice or
contextualize it in the same way. If that still feels bizarre,
because I know it did for me, think about learning a new language. At first, everything just
looks or sounds like gibberish. You can't tell the verbs
apart from the nouns, let alone one word from the next, because you are just learning. But slowly over time, your
brain starts to pick up on these categories and patterns and can recognize minor
differences much faster. It's not like you couldn't tell the words were different before, but it all sort of blended together. Once you become more familiar with it, you start to see and hear
those words much more clearly. Honestly, it's kinda like when
I learn a new English word and then suddenly I hear it everywhere, I see it everywhere. But the truth is I probably
came across that word before but just didn't notice it. But now that I've surely learned the word, the feedback loop is there
and so I truly notice it. It's a wild example of
how our amazing brains have allowed us to create language, but then that language turned back around and has an impact on brain function. Not only is our perception
of the world an illusion, our brains are an active
part of creating it. Thank you so much for watching. I hope you found it as
interesting as I genuinely did. If you like our videos,
make sure you're subscribed, make sure you leave a like on this video, and you can join our mailing list with the link in the description. Otherwise we will see you next
time for a new science video. Peace.
There is a Vox videos about this also. And i remember from an humberto eco reading that he states how red was considered the color, at the point that that's how in spanish it's colorado to say that it is reddish.
here is the vox video https://www.youtube.com/watch?v=gMqZR3pqMjg
SciShow's take on the colour blue. https://youtu.be/9cdoPD51bng
So, they didn't have a word for blue. So the title is a lie then.