Perhaps it could be said, as Descartes noted, that most people never take the time or effort to really get down to the nitty-gritty and examine their own ethnocentric beliefs. I think that Descartes' assersion is that if they did, no matter what they were taught, the beliefs they would end up with as "clear and distinct" would match up with what other people who had also examined their own beliefs in the same manner came up with.