In some societies and among some anthropologists, color terminology (or colour terminology) was used to label races, sometimes in addition to a non-color term for the same race. Identifying races in terms of their skin color has been common since at least the Physiognomica falsely attributed to Aristotle.

Other scientists were more cautious about such categorization, and Charles Darwin argued that the number of categories, or in this case the number of different colors, is completely arbitrary and subjective. For example, some claimed three distinct colors, some four, and others have claimed even more. In contrast, Darwin argued that there are gradations, or degrees between the numbers of categories claimed, and not distinct categories, or colors.