When I was ten, I fell into the novels of Edgar Rice Burroughs. With him, I fled the dinosaurs of Pellucidar in the center of the earth; in the company of the anthropoid apes, I sought the fabled jewels of Opar. I wondered at the hurtling moons of Barsoom, and gasped for oxygen in the thin air of that dying world. When a storm blew my hovercraft off course in the east Atlantic, I crashed in an England dragged down into barbarism by a savage Great War that had dragged on for decades. One summer day, in a brief break from the books, my brother and I even laid out a board and improvised pieces so we could play the Martian game of chess the author had so lovingly described.

A Burroughs hero usually had to learn a new language, and quickly, simply to survive. A lovely girl who could only be wooed in her own tongue often gave a special urgency to the task. This crucial process followed a simple pattern: The hero pointed to objects, gave the English word, then heard the foreign word in reply, hi the novels, this occupied a page or two at most: no fuss with case or gender, no grappling with irregular verbs. Only someone who has struggled to learn a new language as an adult can give this fantasy the bitter smile it deserves.

Burroughs’ books were written for boys, but in them he revealed a great, dark truth of life: We all spend much of our lives among people who don’t quite speak our language. Twenty years out of Texas, my accent still claims me every late night. For five years after college, I had to fight not to use a slang that only the residents of a particular dormitory, from a particular time, would have understood. When my son, heir to my bad habits, came home from three weeks of an academic camp, his conversation was drenched with the idiosyncratic phrases of another group of boys.

When I teased an Argentine friend about the rhythm and pronunciation of her Spanish, the conversation hurled me into an isolated, exotic world that reminded me of Burroughs. As we ate ice cream in a mall, she described a Buenos Aires that was as mysterious and fantastic as distant Barsoom. She told stories of hyperinflation, and the catastrophic return of Juan Peron; of ice cream eaten on hot summer nights at Christmastime; and bits of gossip about her country’s dictator, invited to her wedding. She hadn’t known the desaparecidos, the vanished victims of Argentina’s “dirty war” honored by the outside world; she had been raised among the people who had made them disappear. She thought of the soldiers responsible for the disappearances as fathers and husbands, and explained that some of their children were the orphans of the desaparecidos.

In the United States, we often speak of Latin America as if it were inhabited by a single, cohesive people, but history and geography make other groupings, limited as those may also be, more reasonable. Music, style, and celebrities usually pass easily among the countries that once constituted the nation of Gran Colombia: Venezuela, the diminished Colombia, and the others in the northwest corner of South America. But the Argentines mix poorly with the Gran Colombians, and the short, stocky Central Americans remain isolated from the rest. Dominicans or Puerto Ricans may revere a singer from Colombia’s Cali, but the Gran Colombians look down on the ranchero music and cowboy hats, boots, and silver belt buckles of northern Mexico.

Argentina and Uruguay, in turn, are nearly a separate subcontinent. Formidable barriers isolate Argentina and Uruguay: to the east and south, the ocean; to the north, the Brazilians, speaking not Spanish but Portuguese, and Paraguay, yet another special case; to the west, the highest mountains in die New World. Most of the Argentines and their neighbors on the Rio de la Plata are not mestizos—descendants of the Indians and Spanish—as are so many of the Gran Colombians. Rather, they are descendants of Germans, Italians, Spaniards, and Englishmen. In Argentina, an Italian surname is more common than one from Spain. My friend Fernando, a native of Mendoza at the base of the Andes, loves soccer, but the English game of rugby is his favorite sport, and pictures of him in a blood)’ high-school jersey reflect the depth of his passion. The Argentines’ emotional distance from their neighbors is reflected in jokes: “Why do Chileans love the tango? Because at the end of every tango, an Argentine dies.” “When is an Argentine being unfaithful? When he quits looking in the mirror.”

A Burroughs hero from Colombia, finding himself in Argentina, might want to start pointing and saving the names of things, hoping someone would teach him the proper word. In their homes or on the radio, my Argentine friends heard a Spanish unique to their country, not the language we Americans learn in school. To me, their Spanish has the inflections and rhythms of Italian, not those of the Spanish spoken in Spain, or even in Gran Colombia. My friend Cristina had to be taught the niceties of international Spanish; when she reminisced with another native of Buenos Aires, the two women rolled their eyes and groaned about classes in “Castilian.” The present perfect, a comfortable, familiar construction for the Gran Colombians as well as speakers of English, exists in die far south in books but is rarely used. The Argentines even have a pronoun no other country uses: the informal you is rendered vos, not tu as in the rest of the Hispanic world; and vos has a conjugation only the people of the southern countries know. Once my friend spoke to her little girl using vos, then turned to me, paused, refocused, and spoke to me using tu. I could all but hear the shift of gears: I speak Colombian Spanish, not Argentine.

Buenos Aires, with its many millions and its history of tension with the countryside, even has its own dialect, lunfardo, with verbs unknown outside of the pampas nations, and playful variants of Spanish nouns. In Buenos Aires one may be best served by requesting feca, a reversal of the syllables of the Spanish cafe, when ordering coffee. (In Buenos Aires, I think that I might point, say “steak” in Spanish, and hope for the best.) In recent years, lunfardo has spread throughout much of the country.

A grammarian might consider the Spanish of Argentina a sign of laziness, but it is other tilings as well. In the far south, a new language threatens to enter the world, just as Spanish and Portuguese, neighboring languages with no Andes to climb, once separated centuries ago. In the recent past, we have seen fiercely guarded borders melt, then be redrawn; the Northern Italian struggles to understand a Sicilian: Why not a new language for a distinctive people?

We heirs to the language of Milton and Chaucer find ourselves in the grip of the same process. I can read the novels of Chinua Achebe in the original, but the spoken English of West Africa or even Jamaica is at times nearly incomprehensible to me. Recently, I told my son, “ICQ is a cross between AOL’s instant message and a chat room, but you can use any ISP to log on.” Ten years ago, that sentence would have been nonsense. My son simply nodded.

Language joins, but language separates. When people form a cohesive group, their very union separates them from their neighbors. The Argentines, linguistic penguins riding on an iceberg that has calved from the mainland, have begun to drift away from the Gran Colombians. If the process continues, the people of the pampas will not be able to read the works of any future Gabriel García Márquez of Colombia except in translation.

We can think of this process as entropy, the inevitable falling apart of any human thing, or another of the countless meanings of Original Sin, but the slow ubiquitous metamorphosis of human speech reflects the vocabulary of the heart. Linguistic species emerge, evolve, and disappear. What Burroughs did not tell me is that the isolation people suffer because of the existence of multiple languages is their own doing. Passed through the minds and tongues of many, a language is shaped like a rock in a river. No conscious choice is involved; how we speak and the things we want to say grow naturally out of living in the midst of our own people. A people’s mores, institutions, and language grow organically, and short of outright conquest, no outsider with a desire for order or for being “reasonable” can dictate these things.

In Argentina, there has been a serious outbreak of human nature. The Argentines are occupied with living their lives, and in so doing slowly distance themselves from the other half-billion of the earth who speak Spanish. They cannot help it, and mean no harm. It is just that, for my friend, there is no dance like the tango, no accent that sounds quite right that does not come from Buenos Aires—and, truth be told, just her part of Buenos Aires. She feels these things intensely, just as any resident of distant Opar would tell you, with passion, that there are no jewels to rival those from home.