"The book is orange, purple, and yellow."
Translation:La libro estas oranĝkolora, violkolora kaj flava.
You are correct to say they are different. That difference matters to a lot of people who manage color in some way in their daily lives. But the vast majority of people make no distinction between the two. (much to the annoyance of those who pay attention to such things) The Duo Esperanto crowd, and perhaps Esperanto itself follow on with this widespread tradition.
There is a language, from the Malaysian area, which does not differentiate between blue and green. The people who grew up speaking this language cannot clearly tell the difference. The trees and the sky are all the same color to them.
On the other hand, there are people like me who can see a color or so into the ultraviolet. (I lose a little bit of the red band to do this) I'd love there to be a word in Esperanto for this color (I stole one from Sir Terry Pratchett & call it "octarine", hmm "Oktarina") but I don't expect much use for a word which only about 1 in 1000 will need.
Blue is one of the last major color words to come into a language. It seems clear from the study of ancient languages where the word for blue was not available that its absence was directly connected to their inability to distinguish it.
Classic Greek at the time of Homer did not have a word for blue. At first, scholars thought that their must be frequent occasions of genetic pools where blindness to a particular color was widespread. Genetic studies have show that this is not true. Subsequent experiments have shown that people who have never learned the word to identify a particular color are unable to distinguish it without training.
The above was the subject of a TED talk so I am unable to document it.
I do know that the Innuit have multiple words for snow that identify what they see as obvious features. Non Innuit are unable to see those features. We can see dry, light powdery snow or wet, heavy snow and that's about it.
You raise a good point. As does FredCapp.
Since Innuit languages combine words, it seems like really they are just different ways of expressing much the same thing in a slightly different way.
When the Innu form a compound word from ice that designates early (the first thin layer) ice on fresh water and early (the first thin layer) ice on salt water, they are not just using a different descriptor for the purpose of clarity.
The two kinds of ice look different, sound different when breaking, feel different, taste different, behave differently. And because salt water and fresh water freeze at different temperatures the words speak volumes about the time of year, climate and survival requirements. All of this is immediately apparent to the Innuit speaker but not to non Innuit speakers. For non speakers it requires considerable training to be able to identify the characteristics just by looking at it, that the words designate. They are just not normally visible to English speakers.
I spent several years working in extreme northern conditions. Much of the year involved living and working in several feet of snow and temperatures well below zero for months. When told of an Innuit word that combines building material with snow, we readily understood the concept that some snow was better than some other for building shelter. But for the life of us (and it would have been if we ever had been forced out our western household living arrangements) we English speakers could not see that quality of snow that was highly visible to them.
Were you in Canada? I understand Yupik and Inupiat emphasize differing aspects of the environment. I must admit that I'm dealing with a couple of decades of not ever using the language I only sorta learned, and I'm trying to recall the difference between "fresh water ice" & "salt water ice" (& good for hunting seals on ice.)
I lived with the Inuit of Western Alaska for a time. As Mailman indicates most of their words for snow, and ice are agglutinations. There is ice that a child can walk on, there is ice an adult human can walk on, there is ice which will crumble with a little pressure. There is snow that is wet, snow which is dry, snow which makes good iglus, snow which packs well, snow which blows in the wind, etc. and all of their words pretty much parse out that way.
Every language has terms and expressions which do not exist in other languages, English has tried to remedy that by stealing them from other languages, so we have Karma, Ramadan, raccoon, mukluk (which really means "walrus" in Inuit), etc. Esperanto has tried to remedy that by allowing agglutinating words, the inclusion of neologisms and occasional outright theft of a concept from a national language.
As for color inclusion into a language, I cannot speak on that. The Inuit I knew were very familiar with blue, but their word for green translated "the tundra in spring" Purple was the same word as "blueberry," but I do not recall a word for orange, except for the fruit which was, obviously, imported.