MOST people reading this column will surely agree that people who wish to change their gender should have the freedom to do so.

We’ve come a long way since the days when people with non-heterosexual lifestyles were discriminated against or vilified. Live and let live.

If some people who were born as men wish to live their lives as women, good for them.

And there’s no “but” coming here. Transgender people should have full democratic and human rights, and I wish them all happiness.

I know people who have undergone gender reassignment and I know what it means to them.

One of the curious things about the Gender Recognition Act, which allows men to declare themselves legally as women without any medical intervention or complex certification, is that the public consultation period for it came and went in March with scarcely a murmur.

Governments and parties have largely endorsed the objectives of the trans movement. Only now, after the event, has any real debate about it begun.

I suspect people reading this column would also agree that there is an essential difference between a genetically-endowed woman and a man who thinks and behaves, or in the jargon “self-identifies”, as a woman.

Sex is a biological reality which is essentially unalterable. No matter how many cosmetic changes a man may undergo, they do not actually become a woman. Their DNA remains different: XY instead of XX.

They do not have a uterus and do not menstruate. This is not a reason for transgender women to be vilified or suffer discrimination, it is just a scientific reality. Gender is fluid, but sex is not.

Except that for many trans activists, sex is no longer a physiological matter. When they say that “transwomen are women” they mean it literally, and women who object to this are very often attacked as being transphobic.

The feminist author, Germaine Greer, was widely condemned, and subsequently “no platformed” by many university campuses, because she refused to accept that transgender women are women in a biological sense. For this she is called a “TERF”: a Trans-Exclusionary Radical Feminist.

Now, I was aware of the “TERF wars” on the internet, and regarded it all as a rather silly. As far as I understood it, the Gender Recognition Act was an administrative matter, about making it easier for trans people be legally recognised.

It never occurred to me that it was about altering the very definition of a female, such that man born of woman, could actually become one.

But that is how it is now being interpreted by many transgender groups, for whom it has become an article of faith that a transwoman IS a woman.

This has been made brutally clear to me since I was approached by academics from Edinburgh University concerned that my successor there as rector, Ann Henderson, had been accused of “transphobia” merely for retweeting a parliamentary meeting about the GRA, attended by feminist groups, like Woman’s Place UK, who are concerned about self-identification.

The university’s response was curious. Far from defending her right to freedom of speech, and rejecting the smear of transphobia, it resorted initially to boilerplate language about “zero tolerance of transphobia”.

I have now discovered that anyone who does not give unqualified endorsement to the phase “transwomen are women” will, like Henderson, be accused of hate speech.

And this not just by student unions and extremists on social media. Politicians I respect, like the Scottish Green Party leader, Patrick Harvie, seem to adhere to this dogma.

As one commentator put it, “it is the literal definition of transphobia” to quibble. Needless to say, if I were to be asked to speak in the university where I was formerly rector, I would be no platformed, because I do not accept that biological sex can be altered by an act of creative or legal imagination.

Intolerance has infected this debate to such an extent that it is almost impossible now to discuss it rationally.

Since I became involved, an extraordinary number of women have approached me privately saying that they have been silenced. This includes politicians, academics and media figures – hardly shrinking violets.

University staff and teachers say they fear they’ll be accused of “hate speech” and will lose their jobs. Legal experts will no doubt insist that there are no such hate speech crimes.

However, with the police very publicly urging “victims of transphobia” to report “hate incidents”, many organisations, understandably, are under the impression that transphobia is against the law. It is at any rate regarded as a disciplinary matter if such complaints are made about staff.

This is not just about access to toilets. Transwomen have been doing that, quietly, since public conveniences were first installed by the Victorians. You don’t have to show a birth certificate to enter one.

However, many women are, I think understandably, worried about men self-identifying as women in order to access women’s prisons and domestic abuse refuges.

Abolishing sex difference creates obvious anomalies, not least for single-sex pursuits like women’s sporting events or girl guides. These technical issues could probably be resolved, given goodwill. But goodwill is impossible when anyone who tries to raise them is dismissed as a bigot.

Anyway, for many women this is essentially an existential question. If anyone can become a woman simply by announcing the fact, where does that leave women’s status in society?

Women feel they have been fighting a long struggle to establish their rights against the lingering shadow of patriarchy, and they fear this progress could be halted if they are forced to accept an essentially absurd proposition: that men can become women.

And I’m afraid that it is absurd. If we are to change the very definition of sex, such that there is to be no physiological distinction between the sexes, then we are changing the nature of what it is to be human.

That’s why I now realise that this is not a “women’s issue” as many patronisingly believe, but one that challenges us all. We must not allow well-intentioned legislators to make changes which could have profound consequences, at least not without a free and open debate.

There is sufficient doubt about the objectives of the Gender Recognition Act now for politicians to be seriously worried about it. At the very least, it should be made clear in the legislation that the GRA does not undermine women’s unique sexual identity.

Women should not be intimidated into silence, as many have been. To dispute the claim that transwomen are women is not bigotry. To object to self-identification is not misogyny. To oppose the Gender Recognition Act is not transphobia.

Universities like Edinburgh should make clear that they will not accept debate on this to be closed down by groups armed with quasi-legal jargon about hate speak.

I believe this is in the interests of the trans movement itself. The surest way to alienate public support is to perpetrate this anti-scientific shibboleth.

For transwomen to have equal rights it is not necessary for women to be denied theirs. Don’t tell women what makes a woman, they were, after all, born that way.