In his article “Are women adult human females,” Philosopher Alex Byrne notes that people with so-called “intersex” conditions are often cited as if their existence disproves the thesis AHF, which is a conjunction of two claims (reformulating from how he puts it):

(1) Necessarily, someone is a woman only if they are an adult, human female, and

(2) Necessarily, someone is an adult, human female only if they are a woman.

Our “intersex” friends are commonly cited as disproving specifically (1) here. The idea is that such people are neither male nor female, and yet some clearly are women, which shows that it is false that someone is a woman only if they are adult, human, and female (because this woman is not female). Of course, since AHF is a compound of two claims, if one of them fails to be true, then so does AHF.

The so-called “intersex” conditions are many, with some more obvious or more serious or more consequential than others.

But rather than get lost in the complexities of the facts, Byrne does something fascinating: a thought experiment about an imaginary and very thorough “intersex” condition:

Consider, then, the fictional condition Complete Asexual Syndrome (CAS), which occurs in 1 in 100,000 live births. CAS individuals are born without sex chromosomes; in a CAS fetus, the primordial gonads which typically differentiate at around 7 weeks into ovaries or testes instead dissolve. Nonetheless, at birth CAS individuals appear as normal females and have female-
typical play-styles and interests in infancy. Despite lacking ovaries and a uterus, around puberty they develop breasts and undergo regular episodes of bleeding that are easy to mistake for menstrual cycles. All this means that CAS usually goes undetected. Even when a CAS individual seeks medical help for fertility issues, CAS is unlikely to be diagnosed. CAS individuals behave and look just like (human) females. But behaving and looking like a female is not sufficient for being one. By any reasonable standard, CAS individuals are not female. If adult CAS individuals are women, then we have a counterexample to [claim 1 above].

Byrne, “Are women adult human females?” Section 3.2

Byrne goes on to argue that, although it would be reasonable to treat such people as if they were women, even calling them “women,” surely they are not female, and so they would not be a counterexample to (1), which says in part that being a woman requires being female. But if this extreme imaginary case fails to refute (1), then presumably the lesser real-life “intersex” conditions would fail too.

But I think he’s mistaken, oddly enough, about his own thought experiment.

I would say that as described, such people would indeed be women. Why? Since as I argue here, they would satisfy our concept of a woman, which is someone with a certain body type. As described, it seems nature, if I may put it this way, was “trying” to make a normal female. But something(s) misfired. Breasts and in general a female-structured body are produced in cases of this imaginary condition, but no ovaries are.

I think Byrne would agree that pretty much all people would be willing to treat such a person as a female. But this is because such a person would satisfy our ordinary concept of a human female – she would have a body of the type a natural function of which is to become pregnant. She has this body type in the thought experiment even though she has this surprisingly deep “intersex” disorder, CAS. So there would be no need to treat such people as if they were women; they would be women.

Dr. Byrne has crafted (and named) this imaginary disorder so as to fail any biological conception of what it is to be female, by omitting sex chromosomes and ovaries. But it’s not clear to me that a CAS person, as described, would fail to satisfy a correct biological definition of what it is to be female, because of the point about natural functions above.

Despite how they’re often drawn into gender arguments, we ought to remember the facts about actual people with various “intersex” conditions. As one advocacy group observes,

. . . the vast majority of people with intersex conditions identify as male or female rather than transgender or transsexual. Thus, where all people who identify as transgender or transsexual experience problems with their gender identity, only a small portion of intersex people experience these problems.

Intersex Society of North America FAQ

Why is the first sentence true? Here is one obvious explanation: each of them actually is a man or a woman, despite their developmental problem(s).