She paused. “All my life, I trusted that what I read in places like this was accurate; that someone had checked it out. I assumed that doctors were careful people who know a lot more than I do. Then I find these glaring errors, and who am I? I’m nobody,” she said. “How did an article that cites Sports Illustrated pass muster with a peer-review board of scientists?”

That’s an excerpt from Bronwen Dickey’s excellent book Pit Bull. In this particular chapter, a woman who worked in the records department of a sheriff’s office took it upon herself to carefully read the professional literature dealing with dog-bite fatalities, and you’ll never guess what happened next! No, you probably already have. It turned out that she, with no professional credentials but a lot of determination and savvy, exposed how astonishingly careless and slipshod the “experts” had been in constructing the narratives that dominated the conventional cultural wisdom surrounding supposedly dangerous dogs, like the unjustly-maligned breed in question. But this paragraph obviously has a lot of relevance beyond its original context.

To wit: I just recently learned about the Western European marriage pattern. A book I read happened to mention in passing that the nuclear family had been the norm for several centuries, citing statistics from England since the 1700s. After doing some sleuthing, I discovered that this was, in fact, widely accepted among historians. Since the late Middle Ages, at least, that’s been the case.

Now, as I’ve said many times, I’m not highly educated or credentialed. Whatever smarts I can be said to have are due to genetics and the sweat of my studying brow. But I think it’s fair to say that I’m inquisitive, and I read several dozen books every year, almost entirely non-fiction. It’s not difficult to get me interested enough in a topic to read a 300-page book about it on a whim. I’m pretty slutty that way. And yet, despite having been attentive to all manner of cultural and political events and ideas for a couple decades, I had never heard anything to contradict the assumption, originally picked up who knows where, that intergenerational families had been the norm pretty much everywhere, certainly in America, until the post-World War II prosperity allowed people to customize their living arrangements. For years, I heard a steady message surrounding the topics of families and marriage: talk about “the decline of the family” or “family values” is pure right-wing propaganda, nothing but nostalgia for the days when patriarchs could lord with impunity over their women and children. If anything, capitalism itself was forcing families to splinter into the smallest units for easier mobility as they tracked the skittish herds of jobs across the country. Why, only last month, we saw another rote repetition of this tendentious mythology.

But mythology is what it is. And while the precise dynamic of familial arrangements in Anglo-American history isn’t the sort of keystone that forms the foundation of an entire worldview, it’s unsettling to be reminded how often this might be the case, that much of what we think we know is just someone else’s convenient myth which we’ve never had cause or opportunity to debunk. There are so many things we just have to accept as provisionally true, because who has time to diligently investigate every single idea encountered in daily life? And the alternative of paranoid epistemological nihilism is even worse. We can try to surround ourselves with diverse perspectives to increase our collective wisdom, but how do we know what we’re missing until it bites us on the ass?

It’s a funny paradox. The older I get and the more I learn, the more I conclude that a relaxed agnosticism about damned near everything appears to be the best approach. As is so often the case, Montaigne had it right: Que sais-je? What do I know? I can’t even imagine what “facts” I’ll have to unlearn next.