There are mantras. This is one of the mantras.

Trans women are women. I am a woman because I say I am. There’s no getting rid of trans women. If you don’t like it? There’s nothing you can do about it. History isn’t going backwards sorry — shon faye. (@shonfaye) July 25, 2018

“I am a woman because I say I am.” It’s supposed to be, and often is, a conversation-ender. But that seems to be not so much because it’s convincing or persuasive (let alone a good argument) but because it’s a mantra. Repetition makes it true and shouting makes it mandatory – something like that. I googled the sentence in quotation marks and got about 96,600 results, so definitely a mantra.

But it’s strange that it is when it seems so obviously not true. There are some “because I say I am”s that work that way – like “I say I am quitting” for instance. Performative speech, as a linguist friend pointed out. If I say I quit, I resign, I refuse, I object, then that works. “I quit because I say I quit” makes sense. “I apologize” is another, though it’s possible to say it in such a way that it self-undermines. But it’s not the case that saying “I am a _____” necessarily makes me that ______. I could say I’m a government official who has the authority to fire Trump from the presidency, but it wouldn’t get me anywhere, not even if I went to DC and said it to John Kelly.

Humans aren’t magic. We can’t just say things into existence. We can perform certain things with words, certainly, but there are limits. We can’t change material reality just by saying “I am.”