Does the mere existence of intersex people (and people with 1 XX chromosomes, for example XXY) destroy the claim that gender is based on biological sex? Can this be considered a valid exception, and if yes, why exactly?
Does the mere existence of intersex people (and people with 1 XX chromosomes, for example XXY) destroy the claim that gender is based on biological sex?
It does not. The existence or non-existence of intersex individuals has no bearing on gender.
- Categorise people into sex categories.
- Provided that there is at least one gender category, there exists a mapping S → G from sex categories to gender categories. (If you're a constructivist, gender_of := s ↦ "woman" is your witness.)
- This mapping may or may not be what gender is based on. That's an empirical question about the nature of gender, and it's not one that "intersex people exist" is at all relevant to.
Learning about the existence of intersex individuals might make somebody question gender binarism, but that's a different thing to "destroy[ing] the claim". People who care about truth more than certainty might be convinced – or, at least, rendered less certain – but the argument doesn't follow out of logical necessity.
While it's tempting to do (and I have done) so, I don't feel it is right to use the existence of a demographic as a logically-unsound gotcha, especially not without at least mentioning that they've got struggles of their own – which I'm not informed enough to speak on, by the way. Intersexrights.org is a site with loads of resources on this topic, which I hope you'll look at.
Alternatively, there's Wikipedia, from which I quote Mauro Cabral Grinspan:
People tend to identify a third sex with freedom from the gender binary, but that is not necessarily the case. If only trans and/or intersex people can access that third category, or if they are compulsively assigned a third sex, then the gender binary gets stronger, not weaker
Or, if you want a pithy picture, the Phall-O-Meter:
Is gender sex-based, socially constructed or both?
Your title question is much more interesting! Kevin's answer is a good one, but I'll try to answer more briefly.
- Different societies categorise gender differently. Even with all the merging and subsuming of once-distinct cultures that globalisation is causing, traditional third genders are still a part of how society is structured in parts of the world.
- Most cultures have two distinct genders corresponding to human sexual dimorphism.
- I know of no human society that has no gender.
So it's probably "both". In some cultures, I expect gender is heavily based on sex, to the extent that the very existence of trans (especially non-binary) and intersex people is unthinkable – but that view of gender is not the only possible view, so its selection from the space of possible gender systems is a social construction.
It's also worth noting that, for many people who suffer from gender dysphoria, a large part of it is about how they're perceived – by themselves, and by others. What their voice is like, whether they can grow a moustache, how strong they are. If gender were just about the facts of life, I dare say people wouldn't feel this way about things unrelated to sex or reproduction.
And many of these concerns are not exclusive to trans people! I once knew a cis boy who was upset about not being able to grow a beard. Not out of any social pressure – he was from a culture where being clean-shaven was expected, and stubble was seen as a sign of unkemptness – but because he really wanted to grow a beard. (Maybe he wanted to be a philosopher?)
I am tempted to make the stronger claim, that gender is:
- partly sex-based;
- partly socially-constructed; and
- partly innate to human psychology.
There is a biological aspect (which we usually call "sex") and a social or cultural aspect (which we usually call "gender").* Although these things are strongly correlated, they are not the same thing. A person's sex is determined by their anatomy, chromosomes, etc., while a person's gender can only be determined by asking them.
Sexes other than male and female are collectively known as "intersex." Genders other than male and female are "non-binary genders" or just "non-binary." Although I would imagine that some intersex people do identify as non-binary, these are two different things. An intersex person may identify as any gender, and a non-binary person may have any biological sex.
Some people claim that the social aspect does not exist, and that we should only concern ourselves with the biological aspect. This is sometimes disguised as a claim that sex and gender are the same thing, which sounds like it's just arguing semantics, when in fact it is an empirical claim about reality. The problem with this argument is not the existence of intersex people, but rather the existence of transgender ("trans") people (i.e. people whose gender does not match their sex at birth). This argument has to claim that trans people do not exist, or else it runs afoul of Leibniz's law (if sex and gender are to be the same, that implies that everyone's sex must match their gender, because identical entities must be indiscernible). The problem is, the existence of trans people is fairly well documented at this point, and so the sex-is-gender argument has to contend that those people are not really trans, but lying about their gender identities.
Unfortunately, this has resulted in a great deal of hate speech directed at trans people. I will not give examples, for obvious reasons, but given the sheer number of people who would need to be lying in order for this argument to work, it is for all intents and purposes a conspiracy theory, which need not be taken seriously.
Sometimes, the sex-is-gender crowd tries to sidestep this problem by claiming that trans people are "confused" about their genders, rather than lying. Plenty of trans people are adults, many of whom are quite adamant that they know their own genders. It seems unlikely that mere "confusion" could result in such strong convictions. In response to this, the sex-is-gender crowd will sometimes resort to accusations of mental illness, but to the extent that mental illness is even relevant (in the form of gender dysphoria), the American Psychological Association recommends a treatment of affirming care, i.e. recognizing and affirming the person's gender identity. Attempts to suppress gender dysphoria or change a person's gender identity have generally been ineffective or harmful, and are now regarded as tantamount to conversion therapy. On the other hand, there are established methods of changing a person's sex, usually through some combination of hormonal treatments and surgery, and these are effective treatments for gender dysphoria in many patients.
* This is a simplification. Gender can be further broken down into gender identity, gender expression, gender roles, and a variety of other elements. Similarly, there are different ways of determining a person's biological sex, and they won't necessarily agree with each other. Different cultures have different ways of contextualizing gender and sex, and not all societies adhere to a male/female gender binary in the first place.
Let's define some terms here. When we talk about biological sex, there are several things we could be talking about:
- Primary characteristics: Does the organism in question produce spermatazoa or ova? What gentalia does this organims have?
- Secondary characteristics, for example, in birds, plumage, in mammals, the development of facial hair or functional mammary glands.
If an organism has secondary characteristics of one sex, and primary characteristics of another, we can't really handle that in a binary sense. If an individual produces no gametes, we can't define that individuals sex. Such individuals do exist, therefore the idea that biological sex is strict binary is flawed.
When we talk about gender, we're talking about social roles, expectations, behavior, but most of all about an individuals internal sense of what their gender is. I am, personally, a materialist, so if an individual has an internal sense of who they are, in my world view, that must be in some way dictated by the physical person, by things like brain structure, hormones, or life history. The existence of people who have primary and secondary characteristics of one sex, but an internal sense of belonging to another sex, therefore shows that the idea that primary and secondary sexual characteristics determine gender identity is flawed.