Advanced Search

How are we to define colors? I have two suggestions, but I don’t know where to go from here: (1) they could be defined based on the particular subjective experiences (particular qualia) themselves or they could be defined based on the descriptor or color attribute that one applies to an object. For example: does the sky appear blue to me if and only if the sky gives rise to a particular color experience or does the sky appear blue to me just in case I (or a society) attribute “blue” to the sky regardless of the actual experience that I (we) have? Under the first definition, we only agree that the sky is blue if we actually share the same color experience whereas the second definition does not require this subjective similarity.

There are a couple of ways we might go here. Thinking about the sky, it's a pretty good bet that most people with normal color vision (roughly, people who can pass a color-blindness test like this one ) will say that the sky is blue and will agree that a good many other things are blue, even if they've never seen them before. And so while there is a certain amount of arbitrariness and convention in just where we draw the lines between colors and while the names themselves are certainly matters of convention, there are facts about human physiology here as well. Thus, one way to think about colors is in terms of the responses of "normal" individuals in "normal" conditions (where both of those "normals" are not altogether easy to pin down.) Another way is to think about the physical characteristics of the things we apply the color words to. For example: light with frequency around 450 nanometers is blue light. If the light reflected from a body has this frequency, we call the body blue. But things...