JK Rowling recently drew fire on social media for tweeting the statements to the effect that “biological sex is real.” The tweets began when she mocked an opinion piece that used the term “people who menstruate” in place of “women” to account for the fact that transgender men also menstruate, and prefer not to be described as women.

The backlash on Twitter has been swift and cacophonous, and headlines have followed. GLAAD, an LGBT advocacy group, issued a response on Twitter, calling Rowling’s tweets “inaccurate and cruel.” One commenter wrote “I know you know this because you have been told over and over and over again, but transgender men can menstruate. Non-binary people menstruate. I, a 37-year old woman with a uterus, have not menstruated in a decade. Women are not defined by their periods.”

Till now, even the most thematically ambitious feminist theorists have acknowledged that sex itself is a real biological phenomenon, and that sexual dimorphism is an important component of human existence as well as human rights. Yet increasingly, such common-sense propositions as JK Rowling’s are now cast as hate speech.