A lot obviously depends on what you mean by "colour." (I'll assume "we" means human beings taken collectively over time and space!) If you take a physicalist/reductionist approach and identify colours with some property or properties of light or electromagnetic radiation within the visible spectrum, then, roughly, we might say "no" -- very plausibly light of every frequency (say) in the visible spectrum has causally interacted with the visual system of human beings causing a relevant visual experience etc. But if visual experience is more complex than that -- and it is -- perhaps there are all sorts of combinations of frequencies (and intensities etc) that we have not yet come across, which might even produce different kinds of visual experiences than we've had to date, turning that no into a yes. And surely that initial no is a kind of boring answer, and probably you have in mind something more expansive in asking your question. Perhaps (for example) we can imagine colours corresponding to parts of the...

A deep rich complicated question! A short (too short) answer would go with both, depending what you mean by 'color.' There are subjective aspects to color (perceived color), and there are objective aspects (physical properties, light properties, etc.). The big question of course is just how these two aspects are related. Are they independent in some sense, or intimately related, and if so how? Can perceived color, the perception of color, be identified with or reduced to objective properties, and if so which? There is a ton of literature on this, but you might start with the classic Larry Hardin's "Color for Philosophers." hope that's useful -- to start ap

A deep rich complicated question! A short (too short) answer would go with both, depending what you mean by 'color.' There are subjective aspects to color (perceived color), and there are objective aspects (physical properties, light properties, etc.). The big question of course is just how these two aspects are related. Are they independent in some sense, or intimately related, and if so how? Can perceived color, the perception of color, be identified with or reduced to objective properties, and if so which? There is a ton of literature on this, but you might start with the classic Larry Hardin's "Color for Philosophers." hope that's useful -- to start ap

This is a great, deep question that others will be far more qualified than I to answer appropriately. But one might perhaps start by simply recognizing a fundamental ambiguity in the notion (or meaning of the word) "color." Sometimes by that notion we imply something we take to be physical in nature, a physical property, or a property of physical bodies (or perhaps of light itself), something objective; on that view arguably black would not be a color (if indeed blackness is the absence of all light, so there would be nothing there to have that color). (I actually think that in the complete absence of light human beings see a kind of gray rather than black, but never mind.) But sometimes by "color" we mean something 'mental,' something subjective, something perceived, and here we would likely take black to be as genuine a color as any other, since we can perceive it. Of course it turns out that color conversations quickly get a lot more complicated, because it is not at all straightforward to identity...

Great set of questions! Lots of literature for you to investigate (starting with Hardin's "Color for Philosophers"...) But let me just say briefly here that one typically begins by distinguishing clearly and purely physical properties (like "wavelengths") from "perceived color" -- for there are many demonstrable cases where a given perceived color can NOT be matched or mapped onto any given wavelength(s), and vice versa. Once you make this distinction then it is easy to hold that wavelengths (plus other factors) CAUSE perceived color, or at least are a causal factor therein, but are not identical to them. Then you will begin to ask whether perceived color can be identified with any clearly purely physical properties and will probably find out that the answer is no. (Or if so, it might end up being a brain property -- ie when you perceive color x you are always in brain state y etc. -- but that is a far cry from what we want to normally say about colors, namely that they are properties of surfaces of...

A classic question, which has been MUCH discussed over the centuries -- especially with the rise of early modern philosophy and science (16th-18th centuries) -- rather than give 'the' answer let me mention some historical resources -- beginning at least wiht Galileo but especially prominent with figures like Descartes and Locke, it was recognized that colors don't fit easily/naturally into what were understood to be the genuine physical properties of things -- in Descartes's day it was thought that size, shape, and motion essentially were the only genuine physical properties, and if so, then colors -- which do not seem identifiable with those -- must be said to exist at best only in the mind, as perceivers' responses to those physical properties in objects. John Locke in particular offers numerous arguments in support of this view, you can find them easily by looking him up in the Stanford Encyclopedia of Philosophy or elsewhere. But now while our conception of the physical properties of bodies has...