My experience is that a lot of people are completely closed to factual argument. It's like their brains shut down as soon as you introduce a number. They're not necessarily stupid people, just intimidated or untrained in information, and I find it very difficult to communicate with someone who puts equal weight in some pundit saying, "US healthcare is the best in the world" and an OECD chart that shows US life expectancy is 5 years shorter than "peer" nations.