The social class location of an individual is determined primarily on the basis of that person’s relationship to the means of production. The class that buys labor is capitalist, the class that sells labor is worker, and so forth. It may be the case that people can, unlike race (a caste relation), leave the working class and become a capitalist, or fall out of the capitalist class and have to work, but this does not change the structure of a society, since there are still those who buy labor and those who sell labor and, overall, those who buy labor, that is, those who earn their income through profits (which are derived from the labor of workers), enjoy more power and privilege. This is reflected in the fact that government policies reflect the interests of the wealthy primarily, whereas the preferences of the general population, which is mostly working class, have little influence on policy (see Martin Gilens and Benjamin Page, “Testing Theories of American Politics: Elites, Interest Groups, and Average Citizens,” in Perspectives on Politics, 2014). Moreover, because of inherited affluence, which includes social and cultural location, there is actually very little social mobility.
Concerning the functionalist theory of stratification, which is also the classical economic liberal’s perspective, the claim that poverty has always existed is false. Most human societies down through history were egalitarian. Inequality only emerges with the state and religion around 6,000-8,000 years ago. Humans have been around for at least 200,000 years and possibly date as far back at 800,000. And even before then, their predecessors, who weren’t much different than modern humans, also lived in egalitarian communities. Class stratification is, therefore, in the long view of things, a recent development. Put another way, the natural distributions of intelligence and talents do not explain social class or economic inequality.
With respect to race, this interview with the late Richard Lewontin is excellent. So is this interview with Stephen Jay Gould. Lewontin is a pioneer in genetics research and his argument is the state-of-the-art. Race is a social construct, and it is constructed by the system of racism, which has two aspects: (1) the ideology of racial classification and associated hierarchy; (2) the structure of social and economic and occupational segregation. Race does not exist apart from these aspects. In other words, race is not a natural category, but an invention. Historically speaking, race is a very recent development, emerging with capitalism (which is itself a new system), and is the result of European colonization of the world and the need to control labor populations. Race was very consciously created by the capitalist class, what Barbara Fields has usefully termed “racecraft” (read an interview here). Colonial powers wrote laws defining and dividing populations and developed an ideological system that explained the system of exploitation in terms of innate racial differences.
A similar argument is made with respect to class when it is supposed that people are rich because they have some biological characteristics that allow them to out-compete others. This is Hayek’s argument in his Constitution of Liberty. Hayek avoids the race question, but the claim that class inequality is explained by biology mirrors the racist argument: if people are poor because they are inferior to those who are rich, and if black people as a group are poor compared to white people as a group, and if this is not because of racism but innate differences, then it follows than blacks are racially inferior to whites. But the explanation for why blacks as a group are poorer than whites as a group does not follow from racial differences because race is not a real biological category. Thus the explanation lies in something else. It is the result of political economy, just as class inequality is the result of political economy (see above).
Finally, with respect to gender inequality, it is true that occupation and life choices explain much of it. Women as a sex-class do appear to prefer work in helping professions (teaching, nursing, etc.). Whether this is biological or environmental, i.e. the result of socialization, or both is not that important in explaining gender inequality. To explain inequality between the groups one must ask why occupations in which women are more likely to work are associated with lower pay and less prestige.
One might use the functionalist theory of stratification to explain that the work that men do enjoys higher pay and more prestige because their work is more valuable to society. But the functionalist theory doesn’t work. We can see why from what I said previously. On a functional basis, what is more valuable to the survival and wellbeing of a society than childrearing, childhood education, and keeping the population healthy? How is a CEO maximizing shareholder profit more valuable than those functions? It’s not that the jobs men do commands higher pay and more prestige because these jobs are more important than lower paying and less prestigious jobs. Rather, the consistent factor in all this is that, generally speaking, the jobs that command higher pay and prestige are the jobs in which men are overrepresented.
Clearly another explanation is needed. Even if the differences in occupation and life choices are attributable to biological differences between men and women, there is no reason why this would explain gender inequality. After all, most human societies were matrilineal and egalitarian. It was not until 6,000-8,000 years ago that gender inequality emerges. It is with the emergence of class inequality, the state and law, and religion that we see gender inequality. Economic-class and sex-class inequality appear roughly the same time in history throughout the various civilizations They are historical developments, not natural facts. Same with race, also not a natural fact, which only emerges within the last 500 years as a capitalist strategy to control the working class.