I'm glad you brought that up.

I've thought about this a few times, and I agree with you that it promotes sexism and is bad, but I just really hate using the phrases "he or she" every time I have to use a pronoun. A sentence like "A rationalist should ensure he or she justifies his or her opinion to himself or herself" is just too awkward to understand. And I am too much of a grammar purist to use "them" as a singular.

I used to use the gender-neutral pronoun "ze", but people told me they didn't understand it or didn't like it or thought it sounded stupid. And I tried using "she" as the default for a while, but people kept getting confused because they weren't expecting it, and trying to figure out where I'd mentioned a female.

I'm willing to accept whatever the common consensus is here. Maybe Less Wrong-ers are open-minded enough to accept "ze" where the average reader isn't.

(I've heard some people here use "ve" a few times, but from the context I gathered it was more of a way to refer to aliens/AIs/transhumans than a normal gender-neutral pronoun. Is this true?)