There’s a grandmotherly American adage about religion—that it’s impolite to talk about faith in public. It’s as much a self-fulfilling prophecy as a social convention. If people decline to discuss religion out of a fear of being impolite, their collective silence might make it easier to think talking about religion is, in fact, impolite.

A significant number people in the U.S. do seem to feel this way. According to a new Pew Research Center study, only a third of Americans say they talk about religion with people outside of their families at least once or twice a month. Evangelical Protestants and people who attend historically black churches are far more likely than other religious groups to talk about faith with friends, colleagues, and strangers, but only about half of each of those groups tends to do so with regularity. Jews, Catholics, and mainline Protestants don’t talk about religion much—only a quarter or slightly more of each group said they did so once or twice a month. Atheists, agnostics, and non-religious people were the least likely to discuss religion, with only a tenth or slightly more of each of those groups doing so regularly. All of these groups, outside of those who aren’t religious, said they’re much more likely to talk about religion in private with their immediate families.

For some people, it’s possible religion just doesn’t come up or doesn’t seem relevant. As with any survey, it’s impossible to read any kind of firm causality into these numbers, particularly since the study doesn’t go into why people do or do not talk about religion in public. But the researchers did ask one fascinating follow-up question: What should people do when they disagree about religion?

Sociologically speaking, this is about as close as researchers can get to asking people their opinions about pluralism and dealing with religious diversity. In general, survey respondents were all for engaging people with other viewpoints: Two-thirds said the best thing is to “try to understand and agree to disagree.” But the results get more interesting when they’re broken down by religious groups and denomination. Forty-one percent of Jews said it's best to avoid talking about religion with people who have different views, compared to a quarter of all Christians. People who don’t identify as any particular religion were even more likely to skip the topic: 44 percent said it’s better to stay away from disagreements about faith. And of all Christians, Catholics, at 31 percent, were the most likely to say the same. In general, religious minority groups, or those for whom religion is not a big part of their lives, are the most reticent to get into conflicts over belief.

This seems directly linked to discomfort. Disagreement about religion might mean nitty-gritty theological fights over the nature of grace or Talmud-style parsings of the right way to prepare meat. Or it might mean something more fundamental, like whether God exists or how one gets to heaven or hell. Often, religious beliefs are first-principle: These are the basic views people have about the nature of the universe and their rightful place in it. People don’t necessarily come to these convictions by way of reasoned debate and logical analysis; beliefs can be inherited or intuited or embraced as a matter of faith. If dinner-party guests disagree about religion, it seems unlikely that they’ll come to a resolution about the problem of evil or the nature of salvation over the dessert course. Meanwhile, they’ll be encountering one of the deepest kinds of human differences: what their friends and acquaintances think about existence, morality, and meaning. That’s intense and personal territory, which may seem like a tonal mismatch for the benign chit-chat that carries most public interactions—and it’s also uncomfortable. Instead of revealing commonality, these conversations may create a sense of distance. That distance can be particularly tough to navigate in the face of firm beliefs about topics like salvation and morality; a difference of opinion necessarily seems to imply condemnation.

So, some Americans say, avoid the topic. The other option is to go for it. Roughly 10 percent of people who pray daily and attend services weekly say they’d try to persuade someone who disagrees with them about religion, although only a very small percentage of comparatively less religious people said the same. If those folks can manage to incorporate money and politics into their pitches for or against religion, they’ll make for unusually lively dinner party guests.