"Race' may be understood as an essential biological variable, yet the historical roots of race show that it is based on eighteenth-century religious ideas that proved useful in justifying colonialism. The scientific basis of race as "real' was challenged historically and more recently by the human genome project. Social psychologists, however, have tended to treat race as a natural variable rather than a social construction, giving credibility to the problematic concept and arguably supporting racism. Critical social psychologists challenge this use of race and instead address talk about race, demonstrating that it is designed to present speakers as not racist, while simultaneously supporting inequality.