During the 19th century, the Victorians began scientifically labeling their natural surroundings. They came up with 26 elements for the Periodic Table, 7 taxonomic ranks for biological organisms, but only 2 categories for human sexuality: hetero and homo.

Years passed. Alfred Kinsey made a scale; Fritz Klein refined it. Stonewall happened. Then AIDS happened. Somebody drew a chart. It became clear that people weren't behaving scientifically. At last, in 2012, a breakthrough: TV actress Cynthia Nixon declared that she “chose” to be gay.

As a “Het-Been,” Nixon's remarks that no one should “define my gayness” rightly infuriated the marriage equality movement. In many parts of the world, being gay is a synonym for exile, imprisonment or death.

In the sexually schizoid U.S., where marriage lasting between two straight people is mind-boggling in the cities and gay marriage is mind-boggling in the hinterlands, everybody has at least heard of the TV series Sex in the City. Nixon's statements have inadvertently made it possible to have a national conversation about sexual fluidity. So who are these people who claim they can “choose” to be gay or straight?

According to sex psychologist Dr. Hernando Chaves:

“It's not that common for people to move through that process of marriage, kids and family and then leave that previous life in order to pursue a same-sex relationship. For that minority of people who decide to divorce and start a new life with a same-sex partner and different orientation, most of those individuals have been thinking about this for a long time. Those individuals are often …repressing their orientation or their true attraction and arousal. A lot of people are, in my opinion, trying to conform.”

But are the pressures of conformity entirely responsible for this behavior? One of the benefits of lust is that you don't have to guess what it's after. Curves, ridges, flat planes — it will let you know. However, while our fundamental orientation remains fixed, we may waver in our expression.

As Dr. Chaves explains, “How people identify or understand their expression of heterosexuality is much different than what maybe their history or behavior is describing.”

According to the oft-cited Kinsey Report, 37 percent of men have experienced orgasm through some form of homoerotic outlet, but only 2 to 4 percent of them actually identified as gay.

In other words, some people have gay feelings even though they primarily enjoy straight behavior, while others have straight feelings even though they primarily enjoy gay behavior. This is not groundbreaking news for the majority of the First World; it's only shocking in the U.S., where we still largely think Victorian.

Consider American monologist and writer Spalding Gray. A posthumously published collection of diaries reveals that he wrestled with his sexual expression throughout his life. Although he had several long-term relationships with women, he occasionally experienced attraction for men.

He wrote that he was “very confused about my bisexual feelings. If I crave a relationship with a man, I am not aware of it.” However, his homoerotic feelings did not necessarily translate into physical satisfaction. He described his attempt at fellatio thusly: “I found that I was choking on what felt like a disconnected piece of rubber hose.”

Then there is the case of Psycho star Anthony Perkins. Once overhead as remarking that “if a pill existed that could make him like women, he'd grind it into the ground with his foot,” Perkins married a woman years after he had achieved worldwide fame.

The somewhat breathless biography Split Image portrays him as a man who late in life enjoyed intense bouts of sex with women but preferred longer-term relationships with men. He married primarily because his lover Berry Berenson had become pregnant and was willing to tolerate his ongoing male relationships.

Ultimately, Het-Beens are more than the manifestation of sexual ambidextrousness; they are a reminder that private sexuality has very little in common with public sexual identity. Society doesn't break down because Cynthia Nixon is thinking inside the box; it breaks down if she forgets to carry the one on her 1040 tax form.

Regardless, much like thrice-married Newt Gingrich, Het-Beens tend to gross out everyone when they admit how many different people they've screwed over in their quest for happiness. Perhaps American queasiness with the idea of sexual fluidity stems not from the actual act itself but rather from the implied lack of commitment.

No matter what labels we choose, we can't legislate the heart.

Follow@AfterDarkLA on Twitter.

Advertising disclosure: We may receive compensation for some of the links in our stories. Thank you for supporting LA Weekly and our advertisers.