I can talk about Judith Butler and Foucault. Essentialism, which both reject, says that the gender we are born with carries with it genetic components that make girls innately—genetically—"girly" and boys genetically "he-mannish." In this very traditional understanding of gender, girls are born hardwired to be nurturing mothers. It is their "biological destiny" to have children. Boys are born hardwired to become aggressive defenders of these mothers.

People like Butler have pushed back and said that essentialism has no basis in fact. Yes, people are born with certain certain secondary sexual characteristics that make them a girl or a boy (and she is quick to note that some people are "hermaphrodites," born with both male and female organs) but these sexual characteristics are nothing more than sexual characteristics. They have nothing to do with personality. They don't make girls more nurturing or boys more aggressive.

Society, according to thinkers like Butler, is what makes girls passive and boys active. These characteristics are indoctrinated into girls and boys from a very early age from millions of people.

Butler, for example, says that if a tiny girl, from a few months old, is called a girly girl and constantly receives positive reinforcement every time she does something "girly." For example, she may be hearing "oh, look at her, what a little flirt (at six months), or oh, look at her take care of her doll (at a year), or what a sweetie; just like mommy, playing so quietly and nicely in her toy kitchen (at two). The girl will internalize all these traits as good and desirable, and she will try to repeat them to get praise and attention. Likewise a boy who hears from a very early age the approving tones of "oh, what a real boy" he is the moment he waves a stick or throws a ball or does anything aggressive will repeat these actions as often as possible to win attention and approval.

By time such children are two or three, they have been molded—socially constructed or brainwashed—into becoming people who act the way their gender is expected to act. Multiply this by millions and you have millions of two year olds acting in gender-appropriate ways: "sweet little mommies" and "tough little sluggers." People look at that and see so many children at a very young age acting stereotypically "girly" or "boyish" that they say—and believe—that this is how girls and boys are born. But no, theorize people like Foucault and Butler. This is not how they were born. It is not essential that they behave this way. This behavior is constructed by society and it, Foucault especially would say, serves the interest of the state.

Butler stakes out an extreme position in her book Gender Trouble—she argues that all of gender is socially constructed. Others take a less extreme position, saying that some gender behavior may have biological roots but that it is largely socially constructed. It is programmed into people starting when they are babies.

We can take these same ideas and apply them to race. Foucault, for example, would argue that it serves the interests of the people in power to have a criminal underclass. The powerful have to say they want to get rid of this underclass, but they reality don't. They want to nurture it because, for example, it provides a cheap labor pool. So society takes a race and conditions it to behave criminally. Then it goes back and says that the behavior is essential or inborn to that race while it is really culturally conditioned.