The Diaper Principle states that anyone who has seen you wearing a diaper will never be able to see you as a full adult. This includes, but is not limited to, your parents, your older siblings/cousins, your aunts/uncles, your grandparents, and anyone who's ever been unfortunate enough to have encountered Turning Point USA.
The Diaper Principle in action

1. Aaron: I'm 22 and my parents still won't let me stay out past 9 pm and whenever I confront them about it, their response is always the same: "Because I said so"
Barry: Yeah, that's the Diaper Principle in action. Your best bet is to get a job and move out.

2. Caroline: I saw those Turning Point USA idiots on campus today. They were all wearing diapers and chanting "Socialism sucks! Checkmate libtards!"

Donna: Haven't these clowns heard of the Diaper Principle?
by MacarthurSlayerOfThots March 20, 2021
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