We are often asked to believe that transwomen are women. Many people are happy to accept this claim but those who disagree are treated to ridicule or abuse until most dare not speak up. As a philosopher, this worries me. We should be able to question the truth of any claim without causing offence, but I cannot imagine that I will get away lightly from doing so here.

In this piece, I argue that those who think that it is true that transwomen are women do not have a coherent, unequivocal definition of ‘woman’, and thus whatever they do understand by the term should not form the basis of legislation. In brief, if we say that being a woman has nothing to do with having female biology, as is required by accepting that transwomen are women, then there are three unattractive options: (1) being a woman is essentially tied to traditional social stereotypes of what being a woman involves; (2) there is no difference between women or men, or a large number of people are both or neither; or, (3) it is impossible to tell whether someone is a woman or not. None of these three options is a workable definition of ‘woman’ and yet, if we remove external checks on which male-bodied people are permitted to apply for a Gender Recognition Certificate and thereby legally become women under a new version of the UK Gender Recognition Act, the law will be committed to at least one of these three options. As a philosopher, I find it profoundly worrying that the law could be based on such an incoherent definition; at the very least, the application process for a Gender Recognition Certificate should retain the requirement for medical and/or legal approval to lend some credence to the process, although there are problems even with this option.

These definitional difficulties disappear if we admit biological sex as a determining factor of whether someone is a woman. This may still permit some transexuals with severe dysphoria to count as women (if there turns out to be a biological basis for their condition which could be verified), and it is still consistent with insisting that people who regard themselves as transgender should be able to live their lives free of discrimination and abuse.

I would like to emphasise that I have repeatedly asked trans activists who are in favour of the proposed changes to the Gender Recognition Act to provide me with a definition of ‘woman’, or an account of what a woman is, which does not fall foul of my criticisms below. But I have yet to be given any except ones which fall under the unacceptable options (1), (2) and (3).

What’s the problem with transactivism’s understanding(s) of ‘woman’?

(For simplicity, I will mainly use ‘woman’ as my example. But the argument would equally apply to what counts as a man.)

First, it is important to make clear the distinction between biological sex and gender. Part of the acrimony of the debate about the GRA arises because there are different views about what sex and gender are, but currently the law respects this distinction (Gender Recognition Act 2004, Equality Act 2010), so let us start from there. With this in mind, we can use ‘female’/‘male’ to pick out the sex of individuals and ‘woman’/‘man’ to classify their gender.

It is claimed (by transgender people and those who support them) that the gender to which transgender people belong does not match the biological sex to which they belong, or (in more extreme versions of the theory) that biological sex does not in fact exist or that sex is non-biological and determined by gender. In all these cases, a person’s gender is independent of their biological sex: being female is irrelevant to being a woman.

But, once one divorces gender from biological sex like this, it is very difficult to see what the gender categories man and woman are. Either being a woman is associated with gender roles, social roles and behaviour which women typically perform, or it is based on something internal to a person, the feeling of being a woman, perhaps.

1) If we accept the former account of womanhood which considers performing certain womanly gender roles as determining who is a woman, this makes being a woman depend upon a stereotype of femininity such as wearing dresses and make-up, nurturing, rearing children, being emotional and so on. This version of womanhood is regressive, since it is based on a stereotype which females have fought against for centuries now, and would often regard as being imposed upon them rather than being intrinsic to their nature. It is also deeply implausible: engaging in stereotypically feminine behaviour cannot be sufficient to count as a woman, since this would imply that females who break with feminine stereotypes and engage in stereotypically manly behaviour are not women but men. A definition of ‘woman’ which makes many females transgender regardless of how they feel about it themselves is clearly untenable.

2) If we broaden the account of womanhood based on gender roles to say that the categories woman and man are not anchored to the traditional, mutually-exclusive stereotypical roles, then the distinction between women and men disappears. This broader view ditches the traditional restrictive stereotypes and allows that men and women can do anything the other does; but then one can legitimately ask where the difference between them lies. If a woman and a man can engage in exactly the same roles and types of behaviour, and yet performance of that role is what determines the difference between them, then there is no difference between them. (Remember: biology can’t be used here if one thinks that people can be transgender at all.)

3) Given that outward manifestations of behaviour or the performance of social roles does not determine what a woman is, we now turn to accounts which assert that gender is based upon something internal to the individual; a deeply held feeling or conviction that one is ‘in the wrong body’ or that one is a woman (although male-bodied). This version of the definition invites philosophical questions about what this ‘feeling’ is and how we can accurately determine whether it is present.

The biological basis for this feeling is extremely controversial: there are no notable differences between male brains and female brains except size, for instance; and the equivocal evidence which indicates apparent differences between trans women and non-trans males is only seen in those with gender dysphoria severe enough to seek hormone treatment and full surgery, people who are already covered by the GRA 2004. We could allow that it is possible that there is a biological basis for feelings of being transgender in such people, and thus will exclude them from the discussion. But these pre- and post-op transexuals are now a minority in the transgender community, which leaves a large number of transgender people who are not dysphoric with no biological basis for their condition. This presents some serious problems: What is this feeling based upon if it is not biological? Why do people seem to lack this feeling if they are not transgender? How is it different to being convinced one is a dog, or had a past life, or is younger than one’s true age? (The belief that one is an animal is not particularly uncommon among children, but we do not affirm that they are a different species.)

It is extremely unwise to accept any and every individual’s affirmation that they are transgender without further evidence. First, there are good philosophical reasons based in the work of Wittgenstein to think that the criteria for kind membership must be public to be meaningful: ‘woman’ has no meaning if it can mean different things to different individuals in virtue of private, subjective feelings when no-one has a way to ascertain whether the feelings reported by different people are of the same type. Second, as I have shown in research on human kinds, an individual’s affirmation that he or she belongs to a certain kind, or has a certain condition, is unreliable: some individuals say this to deliberately mislead, while others hold a genuine belief about being of a certain kind when they are not of that kind. Social pressures, the environment, and the attitudes of peers and others can influence someone to accidentally self-identify as a group to which they do not belong. People may sincerely believe that they are of that kind, and if accepted into the group, their conviction may strengthen as other people treat them as belonging; in the case of gender identity, they may sincerely believe that they are women and this believe will gain credence if others confirm it, even if they are not. (The fairytale of The Emperor’s New Clothes is relevant here.) Furthermore, other male-bodied people may deliberately self-identify as women in order to gain access to women-only spaces.

This situation presents difficulties both legally and philosophically: eligibility for a GRC should not be made available to everyone who claims to have a subjective feeling that they are a woman. On this account, anyone who says they are a woman would count as a woman, and that seems both dangerous to females and absurd. To avoid these consequences, it is important to retain some gate-keeping procedure which determines whether someone is eligible to change gender or not.

However, even this medical or legal gate-keeping is problematic. In the case of people who believe themselves to have diseases or psychiatric disorders, it is possible to observe and diagnose fairly reliably on the basis of symptoms, and to rule out those who are mistakenly affirming that they have a particular condition. But as we have seen above it is impossible to characterise what a woman is on the basis of gender roles and how an individual acts without relying upon out-dated stereotypes of woman which many women would reject. Thus, unlike in the case of other kinds which humans belong to, there is no external, observable evidence that a male-bodied person is really a woman.

None of the available options (1), (2), (3), or combinations of these, gives a workable account of what a woman is which is not tied to traditional gender stereotypes. There is no feminist way to understand what a woman is in such as a way that it could be true that transwomen are women.

Which alternatives remain at this point? We either need to bring biology back into the picture, so that being a woman depends upon being female (crucially, this does not amount to the gender essentialist thesis that being female determines that one follows traditional feminine stereotypes, but amounts to accepting that womanhood is a version of (2) plus female biology), or we need to be done with gender entirely and say that ‘woman’ picks out neither a natural nor a socially constructed kind. But if we accept this latter view, females still need the protections afforded them in the Equality Act 2010: in the absence of any definition of ‘woman’, women-only spaces would have to become female-only spaces in order to provide the present protection for female adults and children.