POLITE CONVERSATION

We are told it's not polite to talk about Religion, Politics and Money because the conflicting views aren't good topics of conversation. If we don't talk about the dicey subjects which mean enough to us to have a passionate view about then all that is left to talk about are the topics that mean only little to us that whether people agree with our opinion or not it doesn't really matter. Polite conversation is safe conversation but Is it the right conversation? If we don't talk about our difference in opinions how are we to understand our differences?