I like this question very much
lets think about it simply, Colour is an abstract concept. It doesn’t actually exist. It’s our minds interpretation, mechanized via the brain, of what our eyes’ nerves register electro-chemically.
Colour is merely our imaginative interpretation of a wavelength of a electromagnetic radiation, giving us the ability to recognize and give meaning to only one aspect of different objects.
For a new colour to exist, a new wavelength of light must exist that no one has perceived before, but does lie within our visible spectrum. The likelihood of this is negligible.
It seems more likely to me that a child will be born with a slightly expanded visual spectrum, capable of seeing infra-red and ultraviolet wavelengths.
I am sure there are colours that exist that there is no pronoun for. Maroon, Fuchsia… really, what are those besides made up words? I certainly don’t recognize them. Like the pallet of taste… some people’s eyes simply aren’t as refined.
I am reminded of that statement that “white” and “black” are not colours. Because white is all colours rolled up into one, viewed at once… and black is no colours at all. I always disagreed with that argument. White is all frequencies of visible light (not colour)… black is an absence of visible light (not colour). Colour is how our brains/minds interpret what our eyes do/don’t register.
hope it is clear now 🙂