Racialism entails a belief in the existence and significance of racial categories, but not necessarily in a hierarchy between the races, or in any political or ideological position of racial supremacy. One racialist position is the controversial claim of a measurable correlation between race and intelligence, or race and crime. Less controversial observations on correlations of e.g. race and height or race and disease are strictly speaking also racialist positions.
It is important to note, however, that this distribution of meanings between the two terms used to be precisely inverse at the time they were coined: The Oxford English Dictionary glosses racialism as "belief in the superiority of a particular race" and gives a 1907 quote as the first recorded use. The term racism is glossed by the OED as "[t]he theory that distinctive human characteristics and abilities are determined by race", giving 1936 as the first recorded use. Additionally, the OED records racism as a synonym of racialism: "belief in the superiority of a particular race". By the end of World War II, racism had acquired the same supremacist connotations as racialism: racism now implied racial discrimination, racial supremacism and a harmful intent.
Since the 1960s, some authors have introduced a new meaning for the less-current racialism: Black civil rights activist W. E. B. Du Bois introduced racialism as having the same meaning as racism had prior to WWII, i.e. the philosophical belief that differences exist between human races, be they biological, social, psychological or in the realm of the soul. He reserved the use of racism to refer to the belief that one's particular race is superior to the others (viz., precisely the inverse of the OED definitions). Scholar Molefi Kete Asante criticised DuBois for this definition of racialism in The Afrocentric Idea (1992) where he defines racialism as "...the view…that there are heritable characteristics, possessed by members of our species, which allow us to divide them into a small set of races, in such a way that all the members of these races share certain traits and tendencies with each other that they do not share with members of any other race."
Philosopher Pierre-André Taguieff has used the word racialism as a perfect synonym of scientific racism, to distinguish it from popular racism; He uses the term racialism to mean racism that claims to be scientifically founded. Arthur Gobineau's An Essay on the Inequality of the Human Races (1853-55) is an example of such racialism. Human zoos have been an important component of both popular racism and racialism, popularizing colonialism to the masses and was a subject of curiosity for anthropology and anthropometric studies, until at least the 1930s.
The field of whiteness studies examines the idea that race is a category that only applies to groups that are perceived to be different in some way. This area of scholarship scrutinizes the ways in which white people have become the standard against which all races are marked.
Current racialist positions have moved away from 19th century classifications and rely instead on genetics, studying physiological differences between groups such as race and height, but also more complex, and thus controversial, questions like race and intelligence or race and health.
In the mid-20th century, support for some of the classical terminology of scientific racism declined among anthropologists: scientific support for the "Caucasoid", "Negroid", "Mongoloid" terminology has fallen steadily over the past century. Whereas 78 percent of the articles in the 1931 volume of Journal of Physical Anthropology employed these or similar terms, only 36 percent did so in 1965 (see African-American Civil Rights Movement (1955-1968)), and just 28 percent did in 1996. In February 2001, the editors of the medical journal Archives of Pediatrics and Adolescent Medicine asked authors to no longer use "race" as explanatory variable, nor to use obsolescent terms. Other peer-reviewed journals, such as the New England Journal of Medicine and the American Journal of Public Health, have done the same. The National Institutes of Health issued a program announcement for grant applications through February 1, 2006, specifically seeking researchers to investigate and publicize the detrimental effects of using racial classifications within the healthcare field. The program announcement quoted the editors of one journal as saying that "analysis by race and ethnicity has become an analytical knee-jerk reflex.
Racialist vocabulary with inconsistent definitions is still used in medicine to a small extent, even when it has vanished from some census agencies and everyday speech. Genetics has renewed racialist perspectives, combining with the racialist perspectives of craniofacial anthropometry. Racialism in genetics is criticized as being subjective and otherwise inappropriate, although this tends to be a matter of bias.