So do dark-blue birds against a light-blue sky. Or yellow-green birds, or blue-green insects, against green leaves. That any two things are detectably different shades does not mean that there must be different base color words to describe them.
I’m don’t think that’s correct. In terms of human vision, there are different types of photoreceptor in the eye. They react differently to different wavelengths of light. How the eye reacts to green, and how the eye reacts to blue are qualitatively different.
It really depends on the context. That is what they mean in classical color theory, yes. But, for example, in photographic work relating to white balance, “tint” refers to the color balance being towards magenta vs green. This is similar (if not the same) as the “tint” setting on TV sets, too. And, of course, in everyday speech, “shade” covers both lighter and darker versions of a color.
But, for example, I read somewhere that there was no name for orange - other than carrots, it did not occur very often in old European settings. It was considered a shade of red (hence, “redheads”, those orange-topped critters.)
Similarly, I occasionally argue with my wife over whether turquoise is blue or green… 
Sorta curious how these things are decided. I certainly think of “pink” as a second-tier color, on par with violet or cyan. And really, it only gets that far because pink covers a lot of colors that aren’t “light red”, like magenta (“hot pink”) and lavender. Did someone do a statistical analysis of the English corpus to see which words are most common? How did they decide on a threshold?
What are first tier colors for you? I mean, I would agree about “pink,” but violet/purple, I’m not sure. Unless you make a distinction between violet and purple. (If I had to, I would say violet has more blue to it than purple, but most people I know seem to use them as synonyms.) To me, “first-tier” colors are red, orange, yellow, blue, green, violet. Oh, and brown. ETA: Black, gray, white, too, depending on whether you call them “colors” or not.
In old European settings, not even carrots were orange. Orange carrots became popular in the 17th century because of the Dutch.
Old English had the term geoluread (literally, “yellowred”) to describe the colour before they were exposed to oranges.
Brown might be a better example of a “shade/tint with a different name that we treat as a different colour” than pink is. It could just be thought of as a shade of orange, but it almost never is.
The whole thing about Homer and his “wine dark sea” seems pretty silly to me. No, it doesn’t mean Homer thought the sea was red, or that there wasn’t a word for blue, the point of the phrase is the word dark. The seas was as dark as cloudy sediment-filled red wine, which is what most wine was in Homer’s era. It’s as clear as, er, a light white wine.
Yes, I’m considering violet as distinct here. I basically agree with your list–first tier is red, orange, yellow, green, blue, purple, black, gray, white, and brown. Violet is distinct from purple, but definitely second tier in status.
For what it’s worth, when my daughter was a toddler she had red and yellow and blue and et cetera down cold; show her a green leaf, she’d declare that it was green; the kid was a natural. Anyhow, I asked her what color her hand was.
She looked at me like I was crazy and said “no color”.
Danes call pink lyserød, meaning light red.
I’m sorry, but that makes no sense to me.
That blue and green form a fairly continuous spectrum and that we have representations and understanding of that spectrum doesn’t mean a bright green spring tree against a bright blue spring sky somehow blurs into the same base color. Those are no more “shades” than red and yellow are.
You can randomly break up the spectrum into any sections you want but that is a product of the human mind and cultural learning. I can see teal as a color and blue and green just shades of teal.
Your terminology is a bit misleading. The issue isn’t colour terms, but basic colour terms. That is, colour names which don’t have a more general term. For example, “azure” and “blue” are both colour terms in English, but only “blue” is basic, because “azure” is just a kind of “blue”, but “blue” has no superordinate. It’s theoretically possible for a language with just two basic colour terms to have just as many (or even more) words for describing colour as one with eleven basic colour terms. Such a language could also have terms for “blue” and “pink” and “mauve” and “aquamarine”. The difference would be that all these non-basic colour terms would be conceived as subcategories of “dark” and “light”.
Languages which have only four words for colors will almost invariably have White/Light, Black/Dark, Red and Green as the specific four colors. (Blue can be approximated as a subordinate Green; Yellow as Red variation.)
Thai has a wide repertoire of color words, including several for shades of brown or reddish brown:
- color brown/sugar
- brown with green
- brown with yellow
- light brown
- dark brown
- color pig’s blood
- color mangosteen rind
- color cigarette smoke
as well as words for pink, purple, scarlet, etc.
However, among at least some rural Thais, many colors are still mapped to one of the basic four: White, Black, Red, Green.
Skin is black or white. Thai hair is black (jet black), so even a very dark brown hair color, along with red hair and blond, might be referred to as simply “red hair.” (Such a huge percentage of today’s Thai women dye their hair, that this may be changing.) There are two words for blue, yet still blue things are often lazily called “green.” There is a word for “color transparent” yet transparent objects are often lazily called “white.”
In the New World: Maya Blue.
There are different types of photoreceptor, but they are not narrowband, and they overlap in their ranges of sensitivity, therefore, colour perception is continuous, not discrete.
According to Cecil, orange became orange because of oranges.