P robably nothing in American life has been over-intellectualized so often — or so preciously — as the baseball field. Depending on which writer, academic, or theologian you listen to, the diamond symbolizes the journey that leads you away from home and back to it … or the accretion of life’s failures in pursuit of occasional triumph … or the selflessness of sacrifice … or the narrative of exile and return. The late A. Bartlett Giamatti, a Yale president who went on to serve as baseball commissioner in the late 1980s, compared the baseball field to a garden-like paradise, and wrote of home plate as “the center of all the universe, the omphalos, the navel of the world.” (You’d have to think he knew something about navels, having spent a good portion of his career as a Renaissance professor gazing at one.)

Does this mean we shouldn’t add to the mountain of metaphors that have been heaped onto the baseball field over the decades? It definitely does not. Because whatever else it may be, the ballpark is a reflection of its moment, and in this moment, it reflects the central contradiction of America.

There’s an ugly argument going on right now over what it means to be American. One side contends that America is a place, not an idea — in other words, that it is a country like any other in the world, with a common heritage and culture and language. To belong in America, according to this view, you don’t necessarily have to be white or Christian or a native speaker of English, but you do have to submit yourself to the preeminence of all of these things. A country cannot exist, these people say, if it does not enforce some kind of cultural homogeneity within its borders.

The other side argues that America, alone in the history of the world, is a country defined by common laws and values. This is why we sometimes call it an experiment. By this way of thinking, you become an American by pledging loyalty to the Constitution (rather than to any one leader) and by acting as a responsible citizen. It may just be that the quickest way to success is by speaking English and absorbing the traditional culture, but that’s up to you. The point is that you can live and worship here any way you like, and so long as you abide by the law, you’re just as American as anyone else.

You can fall wherever you want in this debate, but if our iconic baseball fields have anything to say about it, then the answer is unambiguous. On every diamond where adults play baseball, from dusty lots to Dodger Stadium, the infield is governed by a bedrock code of rules: 60 feet six inches from the mound to the plate, 90 feet between bases, four balls for a walk, three strikes for an out. The laws may change from one generation to the next (pitch clocks and bigger bases being recent examples at the big-league level), but they apply equally to everyone, always.

The most remarkable and inspiring thing about a baseball field, however, is that outside of those immutable laws, the ballpark can be anything it wants to be. No two are exactly alike. The crosscut grass may be greener than anything you’ve ever seen, that 90 feet of dirt might be deep brown or clay red, but what defines a field are the quirks that exist within the bounds of play. A football field is 100 yards long and a little more than 53 yards wide; a basketball court 94 by 50 feet. But Yankee Stadium (as any real fan can tell you) is 399 feet to left-center field and just 314 to the short porch in right. Fenway Park is 310 down the left-field line (or 309, depending on who’s measuring), but 420 to the Triangle in center, where the wall suddenly cuts back, like the guy who built it had just staggered out of the Cask ’n Flagon. At Chavez Ravine, it’s exactly 330 down both lines and 385 to both gaps, as if somebody with OCD went crazy with a protractor.

You get my point: To walk into any ballpark is to accept the basic duality of America’s immigrant experience. We love the laws of the diamond for their uniformity, their durability, their inherent fairness. But what makes any field quintessentially American is the thing that sets it apart. It’s Death Valley and the Green Monster, the thickets of ivy and the shadows of catwalks, the totems we hand down to our kids. No park is inherently better or more authentic than the other. Every baseball field on which you will ever set foot, whether ringed by a chain-link fence or by 50,000 shiny seats, is bound by a common project that allows — encourages, even — a measure of self-expression and shared cultural identity.

Is that any less precious a metaphor than talking about the omphalos or the Odyssean trial of baserunning? I’ll grant you, maybe not. But it’s relevant to where we are, and I think Bart Giamatti would have liked it. He was the product of both Italian immigrants and New England brahmins, an Edmund Spenser scholar who lived and died with every ball that brushed past Pesky’s Pole. Only in America could all of that be true.

MATT BAI is Rolling Stone’s National Affairs columnist and a lifelong fan of the New York Yankees. He is the author of The Argument and All the Truth Is Out.