Sex Isn’t Binary And Immutable, But It Wouldn’t Matter (For Trans Rights) If It Were

Katy Montgomerie
4 min readMar 16, 2022

Discussing why I dispute this “Gender Critical” claim and why it’s not enough on its own to oppose trans rights


The general overall “Gender Critical” (GC) argument is:

A) All humans are born with a “sex” property that can only be one of two values and cannot change

B) This “sex” property should be used to segregate people in society, law and medicine sometimes

In this article I’m going to call this property “GC sex”. My argument here is that “GC sex” may be just the same as birth sex, it may be a material property of you today, or it may be a supernatural essence — it doesn’t matter, because (B) is false even if (A) is true.

When you ask GC people what their core belief is, many of them will just say (A), but (B) is a necessary implication. Without (B) why would anyone care that you believe (A) or not. GC isn’t just a belief about the nature of sex, it is also the political argument that the belief (A) should determine law, social interaction and even medicine, which is point (B).

Why (B) Is False

C) The rational reasons that we segregate people in society, law or medicine sometimes is either to address what sexism they face, who finds them attractive, how society treats them or what medicine they need

D) Your “GC sex” observably doesn’t determine what sexism you face, who finds you attractive, how society treats you or what medicine you need.

E) Therefore (B) is false

Justifying (D)

What sexism you face is determined by how the perpetrator reads you. If an individual reads you as a woman and they are a misogynist then they may subject you to misogyny. If a system reads you as a woman and it is misogynistic then it may subject you to misogyny. While it is not true that only “passing” trans women face misogyny, it is much more complicated than that, it is trivially true that “passing” trans women do face misogyny and thus their “GC sex” being “male” isn’t enough to save them and that is all that is required for this argument.

Similarly who finds you attractive and how society treats you is based upon how you are read. You cannot always sense someone’s “GC sex”. It is observably true that some trans women are attractive to straight men, and that society treats them the same as other women. Again it is not true that this only applies to “passing” trans women, but it does at least apply to them and thus that is all that is necessary for this argument.

The medicine you need is determined by your physical (and mental) characteristics. For example if you have a condition that is caused by a Y chromosome, it doesn’t matter if your “GC sex” is male or female, it only matters that you have a Y chromosome, which some people with “GC sex” female (cis women) do have. The only way for “GC sex” to be relevant for medicine is if it is defined just as being the same as a physical sex characteristic, for example if you said “sex is chromosomes”, but then what is relevant is what chromosomes you have, not what “GC sex” value they have been ascribed.

There are other reasons we segregate people than those in (C) for example tradition or religion. While it is important to respect people’s cultures within reason, if they are used to harm people or prevent them living a normal or private life then they are less important than the reasons given in (C). Your religion may claim that trans women have a male soul, but that isn’t a good reason to make them less safe by banning them from the toilets at work, or from blocking them from breast cancer screenings.


It happens that (A) is false, but in a world where it was true why should a trans woman be banned from protections from misogyny when she faces misogyny? Why should a trans woman be denied protections from lesphobia if she faces it? Why should we pretend society treats her a certain way when it observably doesn’t? Worst of all, why should we base her healthcare on a body she doesn’t have?

Sex is real in that sex characteristics are real and they affect your life. It would be possible to construct a definition of “GC sex” that was binary and immutable, but firstly it would inevitably miscategorise some cis people, and secondly it wouldn’t be useful for any of the reasons we care about someone’s sex.

A Katy’s Shit Cartoon arguing that protections from misogyny should be based on who experiences misogyny, not on whatever sex characteristic GC people are pretending is the only important one this week



Katy Montgomerie

Katy is a feminist, LGBT rights advocate, atheist, metalhead, insect enthusiast and trans woman