One of my friends recently stated: "black is not a colour. It is the entire absence of it, both physically and neurochemically." But can this be right? I understand what my friend is saying in that things appear black when they don't emit or reflect any photons of light, and that, as a result, there is nothing for the light sensitive cells in our eyes to detect. However, in everyday life we still view black as a colour, just as we do red or green.
I should probably mention that my friend is a scientist and tends to take a strictly empirical and sometimes rather reductionist view of things. Consequently, I'm keen to get a broader perspective on this question from a philosopher.
So, my question then is: is black a colour? Or, perhaps more accurately, does it even make sense for us not to consider black a colour?
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...