i had an object lesson in this very thing during my early years in undergrad. a history professor handed out a list of essay topics, one of which touched on something i felt strongly about, but argued the opposing side. naturally i asked if i could take on that topic but switch sides; wisely, the professor denied my request. because none of the other topics sparked my interest, i was forced to do actual research into something that i believed to be false. lo and behold, i learned a lot and managed to gain a greater and more thorough understanding of the topic, and you know what? i actually changed my mind — it went from a gut-level reaction to a researched fact-based understanding of a complex situation.
i don’t remember the professor’s name, or very much else about that class, but i will never forget the lesson in arguing the opposing point of view. it’s a lesson i need to keep fresh in my mind these ugly divisive days.