I sometimes get asked why I devote so much bandwidth to challenging the movement that I’ve described as gender cultism—a faddish ideology whose adherents (1) claim that all humans are infused with a soul-like ether known as gender identity; and (2) insist that the self-reported nature of this spirit trumps the objective reality of biological sex.

The most obvious answer is that this movement does real, observable harm, by forcing women to share prisons, rape-crisis centres, athletic leagues, locker rooms, and other vulnerable spaces with men. It also encourages children, many of them gay, autistic, or psychologically fragile due to bullying and underlying mental-health challenges, to indulge the gothic horror-movie delusion that they were “born in the wrong body,” and to embark on a lifetime regime of (dangerous and untested) drug treatments and body-disfiguring surgeries.

But there’s another factor at play, too: I don’t want to live in a society that gaslights its own citizens. The oft-repeated slogan that “trans women are women” simply isn’t true. Furthermore, everyone knows it isn’t true—including those who shout it the loudest. Like other slogans of this type, it’s an officially sanctioned lie. And once it becomes a matter of settled precedent that we can all be forced to submit to this kind of lie, many more of them are guaranteed to follow.