Ancient Greek has no word that maps to blue. Homer's sea is oinopa, wine-faced; his sheep are wine-colored; honey is green; the sky is bronze; kuaneos means dark and covers Hector's hair and Zeus's eyebrows. The New Testament never uses blue; ancient Japanese ao covered blue and green together. The conspicuous exception: Egypt had a blue word, and Egypt was the one ancient culture that could manufacture blue dye, Egyptian blue, the first synthetic pigment. Linguists' rule of thumb: languages name colors roughly as they can make them.
The famous phrase is a translation fossil: oinopa is oinos, wine, plus ops, eye or face, literally wine-faced, and Liddell and Scott fixed it as wine-dark in 1843. Later translators scattered: wine-blue, winedark, the sea's gray wine, or Mitchell's flat the sea. The mystery may be less perceptual than poetic, an epithet about mood, not wavelength. Gladstone and Goethe's verdict, the Greeks were color-defective, has not aged well.
The claim: blue entered languages not when eyes changed but when supply chains did, lapis, Egyptian blue, indigo, ultramarine, Prussian blue, each pigment forcing a word into being, so the bluest sky in history went unnamed until someone could sell it. Verdict: the Egypt correlation supports it and the pigment timeline matches suspiciously well. The sky was free. The word cost lapis. The archive notes the pattern holds: names follow inventory, and the unnamed is not unseen, it is merely unsold.
If the Greeks had no word for the sky's color, what did they see when they looked up?