Pensees - it's either French for "thoughts" or a misspelling of "penises"

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Ranking - it's a very animal thing to do, so it's a very human thing to do. The way we suss out who we are as individuals, on the whole, is by comparison with others. And then we do the same thing bigger as tribes - you're either a villager or a foreigner.
Top Ranking - gi' me little bass, make me wind at me waist.
Seriously though, I think because people on the whole define themselves in relation to the people around them, they find diversity a bit threatening. If you're not "sure what someone is", then you're less sure what you are. But if you don't buy into that too much in the first place, it can just be much more loose and accepting. I guess the reason why you still get a lot of this kind of thing amongst minority groups (such as trans, queer, etc.) is that people who are feeling threatened already by oppression tend to go rigid if they're not careful. So I think the whole "you're only a proper woman/man if..." thing in this context is just coming out of fear - fear of not being accepted oneself, fear of non-acceptance by association, very schoolyard kind of stuff.