At first instinct it looks like a stupid question but the answer hasn’t always been blue.

As humans we have evolved over time we have gained the ability to see that color, blue. This fact is ever present in almost every linguistic system, we only need to see the ancient Greeks and Hebrews. In Homer’s Odyssey, he describes the sea as “wine-dark” rather than blue. Some evidence points to the first mention of the color was made by the Egyptians when they started to produce a pigment calcium copper silicate, also known as Egyptian blue. The ability to see this color comes to us as a classification of language and culture, not by a biological process. If there is no word or way to describe something, how do we confirm or express its existence?.

We as modern humans have a lot of blue pigments so blue things are common to us but blue things in nature are quite uncommon. This led the situation so that there wasn’t a word to describe them in ancient times making the description of the sky to resemble black and green but not blue. It is easy to stand on the shoulders of giants and see further than people before us but understanding the difference in cognition and collective knowledge is to understand the evolution of culture.