By biggest, I mean one that the most of all people assume is true. It can be of anything — race, nationality, faith, religion, subculture, sex, gender, whatever. I’ve heard of that:
Women ain’t as good/smart/strong as men.
Islam is an evil religion (astaghfirullāh).
Hippies have long hair and are dirty.
Gender and sex are the same thing.
The majority of Muslims live in the Middle East.
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