As difficult as it is, I do really like this Brave New World:

Or they may say “Sex is physical, gender is socially constructed.”

This simply isn’t true.

Sex is no more an immutable binary than is gender. There are intersex people who are born with non-binary genitalia, as I have already mentioned. There are people with hormonal anomalies. In fact, hormone levels vary wildly within the categories of cis male and cis female. Chromosomes, too, vary. If you thought “XX” and “XY” were the only two possible combinations, you have some serious googling to do. In addition to variations like XXY, XXYY, or X, sometimes cis people find out that they are genetically the “opposite” of what they though they were- that is, a ‘typical’ cis man can be XX, a ‘normal’ cis woman can be XY.

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