 Controversy over race categories, gender categories, and other categories, pertains both to their construction and their essential properties. The term ‘essentialism’, as applied to categories such as race and gender, has a different meaning than it does in mainstream metaphysics. As applied to race, for instance, ‘essentialism’ is often understood as synonymous with ‘biological essentialism’—the view that races have simple, natural, and heritable biological properties, such that every member of a racial group has that biological property. This should not be confused with a metaphysical claim that might be made by a social constructivist proposing a “social essence” of race: for instance, a claim that membership in a racial group essentially involves identifying with other people for reasons of solidarity, or that it involves being descended from a historically and geographically situated population. Such a theorist would flatly deny “essentialism” in the old sense, which still analyzing the (socially set up) essential properties of race (for a critique of essentialism, see Phillips 2010; see also entry on  race).