The history of Mexican aboriginal classification illustrates the ways in which political interests and power relations operate to produce such classifications as race, class, and ethnicity. Such designations, in turn, produce political frames - a set of problems and solutions - that appear to match the category. The fact that the designation of a single individual or group can shift from one category to another suggests that theorists should not rely too heavily on seemingly objective understandings of what a group is, whether it is a race, class, or ethnic group, to determine the scope and contours of justice.