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 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 color.

But if you were to read Homer, not that one.

The famous ancient Greek writer from the eighth century BC, you noticed 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 colorblind.

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 text to ancient Indian epics dating to about four millennia ago to ancient Chinese writings and even the original Hebrew Bible.

All of them failed to mention blue once, while all of them that mentioned black, white and red and many the Bible included also mentioned 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 blew.

It wasn't until the mid 18 hundreds that linguists began toe, analyze the history of languages and found something peculiar in every culture, black and white.

Our 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 read.

It's often associated with blood or danger.

Even human faces and communication use read 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 to, 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 read being the easiest and most accessible color because you could just take a piece of dry clay and use it as a crayon.

If you think of cave drawings, for example, there's a law of black and red in them but blue.

It's one of the hardest colors to create.

For thousands 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 there, Mork quickly able to note the difference that we wouldn't catch as quickly this one.

And this is because they have mawr 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 18 nineties, 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 Hughes, which we would still call blue.

In that sense, black would have been a much broader term for early in ancient humans.

It's kind of 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 seemed 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 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 our 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 happily sees them as distinct use.

Without the word, you would still see the color, but you wouldn't notice or contextualized 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 downs, 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 kind of like when I learned 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 truly learned the word.

The feedback loop is there, and so I truly notice it.

It's a wild example of how are 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.

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