Though with less fanfare than one might have imagined, Saturday marked the 50th anniversary of the most contested, talked-about, tempestuous, often reviled – and, according to its most ardent fans, also the most misunderstood and underappreciated – papal encyclical of all time, Blessed Pope Paul VI’s 1968 missive Humanae Vitae, subtitled “On the regulation of birth.”

By saying no to the pill, Paul VI not only appeared to defy the expectations of a majority of his own commission of consultants on birth control, but to turn his back on the emerging secular and freedom-oriented culture of the West. The decision set off a tumult within Catholicism that has really never ended.

In a sense, there’s a clear before and after. The post-Humanae Vitae period in which we’re still living is noisier, messier, more turbulent. It’s one in which nothing can be taken for granted, least of all a global Catholic chorus of “how high?” when popes say “jump.”

Today, while some Catholics think of Humanae Vitae as basically a dead letter, there’s also a vibrant minority determined to recover its broader vision of the meaning and purpose of human sexuality and to put it into practice. Those reactions are largely a matter of differing outlooks and opinions, but one point that’s reasonably objective about the encyclical is the way it brought home – or, at least, should have brought home – the distinctively Catholic understanding of law.

It’s a point that’s frequently misunderstood in Anglo-Saxon cultures, including the United States, and in many ways it forms the heart of a well-known “cultural gap” between Main Street USA and Rome.

To this day, polls continue to show that a wide majority of Catholics in the West reject the teaching of Humanae Vitae. A 2016 poll by the Pew Research Forum, for instance, found only 13 percent of American Catholics who go to Mass every week think contraception is morally wrong. At the pastoral level, most priests will tell you that rank-and-file Catholics long ago made their peace with the use of birth control and don’t bother confessing it anymore.

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For many Anglo-Saxons, that’s just an intolerable disjunction between behavior and law, because we’re accustomed to thinking of law as a lowest common denominator of civil society. That is, we expect laws to be obeyed, and when they’re not, we recognize only two possibilities – either there has to be a crackdown, or the law has to be changed.

It undercuts the credibility of the entire system, our culture teaches us to think, if a law is on the books but practically unenforced and widely disregarded. That, however, is simply not how law is understood in the Mediterranean cultures which are the crucible of Catholicism, above all Italy.

The Italian humor writer Beppe Severgnini captures the Italian mindset perfectly in his book La Bella Figura: A Field Guide to the Italian Mind:

Do you see that red light? It looks the same as any other red light anywhere in the world, but it’s an Italian invention. It’s not an order, as you might naïvely think. Nor is it a warning, as a superficial glance might suggest. It’s actually an opportunity to reflect, and that reflection is hardly ever silly. Pointless, perhaps, but not silly.

When many Italians see a stoplight, their brains perceive no prohibition (Red! Stop! Do not pass!). Instead, they see a stimulus. OK, then. What kind of red is it? A pedestrian red? But it’s seven in the morning. There are no pedestrians about this early. That means it’s a negotiable red; it’s a “not-quite-red.” So we can go. Or is it a red at an intersection? What kind of intersection? You can see what’s coming here, and the road is clear. So it’s not a red, it’s an “almost red,” a “relative red.” What do we do? We think about it for a bit, then we go.

And what if it’s a red at a dangerous intersection with traffic you can’t see arriving at high speed? What kind of question is that? We stop, of course, and wait for the green light. In Florence, they have an expression: rosso pieno (full red). Rosso (red) is a bureaucratic formula, and pieno (full) is a personal comment.

Note that these decisions are not taken lightly. They are the outcome of a logical process that almost always turns out to be accurate. When the reasoning fails, it’s time to call the ambulance. This is the Italian take on rules of whatever kind, regarding road discipline, the law, taxes, or personal behavior. If it is opportunism, it is an opportunism born of pride, not selfishness. The sculptor Benvenuto Cellini considered himself “above the law” because he was an artist. Most Italians don’t go quite that far, but we do grant ourselves the right to interpret it.

We don’t accept the idea that a ban is a ban, or that a red light is a red light. Our reaction is “Let’s talk about it.”

That, in a nutshell, has always been the Catholic instinct when it comes to law – “let’s talk about it.” The Vatican forever issues decrees that can seem sweeping, draconian, and inflexible, but that’s because it’s trying to issue law that transcends space (a global church of 1.3 billion souls, spread across wildly different cultures in every nook and cranny of the planet) and time (a tradition that stretches over two millennia.)

Always, there’s a common-sense understanding encoded in the law that pastors will make reasonable judgments about how the law applies in their concrete circumstances. That’s not seen as “disobedience,” but rather good pastoral practice.

In a sense, that’s part of what made Pope Francis’s Amoris Laetitia so incomprehensible for a wide swath of American Catholicism. When the pontiff insisted he was making no change in the law, while at the same time opening a cautious door for its application to differ in a specific set of circumstances, Americans sensed a contradiction – Italians, on the other hand, saw business as usual.

Of course, this is to explain the Italian mindset, not necessarily to defend it. Just as the Anglo-Saxon model can tend toward rigidity, the built-in vice of the Italian way of seeing things is anarchy. It’s also about the cult of the bella figura, of being content with maintaining appearances while on the inside things rot and decay.

Anyone who’s ever tried to park a car on a Roman street where other vehicles are piled two and three deep, for instance, undoubtedly would say that a slightly greater splash of compliance with the rules wouldn’t do il bel paese any great harm.

Whatever conclusion one reaches, the point is that in order to understand Catholicism, one has to be aware of the difference. We probably should have learned that lesson 50 years ago with Humanae Vitae, but it remains every bit as valid today.