Common misconceptions exist in the world, often because the truth is unexpected or unconventional. If you never paid much attention to the vowels at the end of Berenst**n you would just assume they go like most names of that form. You’ve seen the name, so you also assume you saw what you thought the name was.
Technically, the “Mandela Effect” is a claim that the subject is more likely to have unwittingly traveled between dimensions than they are to have misremembered a small detail. Pure solipsism.
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