I make my living as a political scientist, but my big hobby is cycling. I’ve been riding a bike for fun and for exercise off and on for more than two decades now, ever since I was a teenager and first got hooked on mountain biking in the woods behind my parents’ house in Carrboro, NC. Nowadays, I usually spend 10-15 hours on the bike each week, most of it on the roads in and around Washington, DC. I haven’t raced in a few years–a handful of crashes convinced me to get out of the formal side of the sport–but I still do a lot of fast group rides, some of which draw scores of riders when the weather’s nice.

When I’m on my bike, I try to push my work life to the back of my mind and just concentrate on the ride. That, and the exercise, are usually the point of the thing. Still, I’ve spent my entire adulthood training to think like a social scientist, and road cycling is an inherently social endeavor, so the mental firewall sometimes crumbles. When that happens, one of a few recurring themes usually comes to mind, depending on the situation.

1. Rule of law doesn’t mean that laws rule. Social scientists who study political and economic development talk a lot about the importance of “rule of law,” which boils down to the idea that sensible laws are predictably and fairly enforced. According to many development theorists, rich democracies like the United States have prospered in large part because they transitioned early from arbitrary and capricious regulations to rule of law. Poorer countries will only see their economic growth rates take off and politics stabilize, the thinking goes, when they manage to make the same shift.

Even in the United States, though, rule of law can be startlingly incomplete. When you’re perched on a 17-lb. carbon-fiber sculpture, trying to share the road with streams of 3,500-lb. hurtling steel boxes, you’re constantly reminded that the formal rules only tell a small part of the story. Most drivers exceed the formal speed limit most of the time. Almost no one comes to a complete stop at stop signs, even though that’s what the rules of the road tell you to do. (Cyclists are probably worse about this one than drivers, by the way, often blowing through stop signs where cars are already waiting.) A lot of people in Maryland, where I live, talk on hand-held mobile phones while they drive, despite the fact that the state passed a law last year banning that behavior. Some drivers expect cyclists to clear the road for them, even though the law in most (all?) states instructs cyclists to take the lane when the rider judges that it’s not safe to squeeze onto the shoulder. Significantly, this gap between formal and informal rules doesn’t just happen when the police aren’t around. On numerous occasions, I’ve had police officers tell me to do something not prescribed by law (e.g., avoid this road, stay on that bike path), apparently because they thought it was expedient.

If you tried to survive in this environment by counting on people to follow the formal rules, you’d be toast. Some of this is just ignorance of the law, but some of it–like speeding–is the result of informal practices that dominate the formal rules. Some of those informal practices might be more efficient than their formal counterparts, but surely some are not. So, even in places where “rule of law” supposedly prevails, many of our daily practices are still built around shared expectations based on unwritten and sometimes inefficient rules, and these unwritten rules can be very hard to dislodge when they are widely followed.

These observations have strongly influenced how I think about prescriptions for better governance in “developing” countries that are based on changes to formal rules. Some political scientists and economists place great faith in the idea that desirable social outcomes can be brought about by crafting rules that will give people incentives to behave in the ways we’d like. On paper, that idea makes some sense. In practice, however, this yawning gap between formal and informal institutions on the roads reminds me that real life is a lot more complicated.

2. Some people act as if (your) life is really cheap. There are a lot of bad or distracted drivers out there who unintentionally put themselves and cyclists at risk; whenever I encounter them, I might shake my head, but I’m not all that surprised. What do surprise me are the extraordinarily dangerous things some drivers will do to send cyclists a message when they don’t like how those riders are behaving on the road. As far as I can tell, these people just don’t think my life is worth very much, or they just don’t think about it at all.

A couple of years ago, I was on a big group ride in a semi-rural part of Montgomery County on a Saturday morning when a driver apparently got frustrated with waiting behind us for a safe place to pass. On a fast downhill, where our group had stretched into single file and was travelling at or above the 30 mph speed limit, this guy decided to try to pass, then abruptly pulled his car back to the right, splitting the line of cyclists right in front of me. A couple of seconds later, he hit his brakes hard, even though the riders in front of him were still flying down the hill at the same speed. I swerved just enough to avoid ramming straight into his back bumper, clipping the back-left corner of his car instead. My chin hit the trunk, then I flipped through the air and landed on my bum in the opposite lane. Lucky for me, no cars were coming the other way. Without a word and with barely a pause, the driver sped off to his house, which turned out to be just a half-mile down the same road. He pulled into his garage and stayed inside, even when the police came.

That’s just one of many close calls I’ve had on the road with drivers who seemed to be using their machines to tell me how they felt about my presence or behavior on the road. Sometimes it’s just a yell as they pass, but at least a few times a month it’s more: a swerve that squeezes me to the edge of, or even off, the road; a tailgater who could kill me with just a touch of the gas; a guy a couple of weeks ago who sped by, pulled over, jumped out of his car, and screamed at me to come fight him, apparently because I’d delayed him at the last traffic light. (I’ve been part of that particular scenario a few times now.)

It’s hard to imagine that these drivers would engage in these behaviors if they could think through all the potential costs of their actions. For starters, I’d like to think my life is worth something to them, if only in the abstract sense that most of us see human life as a thing worth protecting. Even in totally selfish terms, though, an incident in which I’m badly hurt or killed would be a huge inconvenience for the driver, too. The police, the insurance, the possibility of courts and even jail time–all of that’s going to be a much bigger hassle than the few extra seconds they might wait for a safe opportunity to pass me.

I sometimes think of these angry drivers when I’m reading theories of civil war and other forms of political violence. In the past couple of decades, a lot of the thinking about why civil wars happen where and when they do has centered on the assumption that violence is an instrument which organizations use to advance their political interests, and that individuals who choose to participate in that violence do so after weighing its expected risks and benefits. I still think both of those assumptions can be useful ones for purposes of theorizing about violence, but my experiences on the road have also taught me that those assumptions have stark limits. Sometimes, people threaten or use violence in ways that just don’t seem to take much account of the consequences, and trying to understand that behavior as the product of cost-benefit analysis can take us pretty far away from reality.

3. We all belong to tribes. Cyclists often ride in packs, and the conversation in those packs often turns to drivers. In those conversations, “we” (riders) are typically described as good people doing good things for bodies and our planet, and “they” (drivers) are often described as careless or even bad people who are thinking only of themselves and denying us our rightful place on the road. We share stories of injustices suffered by ourselves or other riders on Facebook and Twitter, and when one of us is threatened by a driver, others often rally around to protect him or her, even if it’s someone we hardly know. That time I clipped the back of a fast-braking car on my Saturday-morning ride, a dozen guys I’ve never seen off a bike stopped their day to make sure I was okay, then waited for almost a half-hour to talk to the police in hopes of punishing the driver.

Based on my limited knowledge of anthropology, I gather this is standard in-group/out-group behavior. We see ourselves as part of a social collective with a distinct identity and way of life; we identify external threats to that way of life; and we go out of our way to protect members of our collective from those threats, even in situations where it isn’t self-evidently “rational” to do so. This is exactly the kind of us vs. them behavior that political scientists and sociologists often describe when discussing “ethnic” or “tribal” groups, usually in pejorative terms. People in rich countries are supposed to have traded in these traditional identities for more “modern” ones, and that break with tradition is supposed to give them the freedom to make decisions based on efficiency instead of obligation.

In short, cyclists may not be an ethnic group, but they sometimes act like one. That cyclists can act like an ethnic group reinforces my belief that the constructivists are right about the origins and behavior of human communities. Supposedly “modern” humans are just the same old people plunked down in different contexts, “ancient hatreds” can get pretty intense pretty fast, and modernity–whatever that is–is not a cure for these quirks of our nature.