Here's where I stand on the whole "we shouldn't acquiesce to mentally ill people and call them the gender that they are biologically not just like we shouldn't agree to call anorexics fat."
You can visibly see if a person is fat or not. If they are bone thin of course you shouldn't agree to call them fat if they insist they are. However, biology is not so easily assessed. It would be foolish to say that gender is black and white when we know for a fact there are mutations among humans all the time. Hermaphrodites are not made up. They exist. There are mixed up genetics all the time that cause havoc in humans where things that should only happen with females can happen to males and visa versa.
How can you truly know for a fact that the person you are addressing that was born and raised as one sex and now asks to be called another has absolutely no mixed biology? Hell I don't think even biologists can fully say for sure since we still don't know conclusively what all constitutes the two sexes when it comes to exact biology. Do you know exactly what their genitals look like? Can you say for sure they have a complete set? Why do you insist to know what true biology they are?
To me it would seem that by at least going along with their request, not treating them differently, and being respectful of their requests so far as what to call them and what bathroom they are in, you would remove all their external excuses for mental anguish. If they no longer can blame their depression on how they are treated by society, then they would be left with only to look inward.
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