Answer on Quora:

For about the 200th time, we don't "change genders." We simply manifest the gender we know ourselves to be. Gender is innate. What gets changed is (sometimes) the hormonal aspect of physiology and (sometimes) the habitus, or appearance. I know this is hard to grasp if you're not trans, but the brain is the seat of the self. And trans brains differ in key ways which impact that innate sense of self.

Do some legwork for pete's sake. Don't just blat ninth grade biology about chromosomes and karyotypes and genitals. If, god forbid, you were in a car crash today and they were trying to figure out if you had any chance of surviving, it's your brain that is the ultimate arbiter of self awareness and identity, not what's in your underpants.

Feel like I've come in half way through a lecture without knowing the subject or any of the initial background or position.
Context is everything, rather than a mere precis.