A biography, according to my American Heritage Dictionary of the English Language, is “an account of a person’s life written, composed, or produced by another.” Yet, in recent years, a number of writers have been stretching this definition. Nowadays, human beings are no longer the sole suitable subjects for a biography, which is coming to mean an account of just about anything’s life, or history, or essence. These things include cities, literary forms, integers, currency, animals, and automobiles, to name a few. Why are people writing biographies of such things now? Is it because contemporary writers are more imaginative and open-minded than their predecessors? Or are they simply more desperate for subject matter that hasn’t already been chewed to death? Or could it be some combination of the two? While I don’t claim to know the answer, I do have a theory that the expanding field of worthy subjects for biographies is related to the expanding field of worthy subjects for serious academic and historical inquiry. The latest example of this high-low trend is Harvard history professor Jill Lepore’s current bestseller, The Secret History of Wonder Woman. It joins a growing shelf of serious books about such everyday objects as salt, cod, pop songs, and the pencil (and, yes, how to sharpen a pencil). Here is a sampling of a half dozen things that have become the subject of biographies by writers who have stretched the conventional definition of the form, to sometimes stunning effect. A City Scott Martelle, a former reporter for The Detroit News, like so many people who grew up in Detroit or spent a sizeable chunk of time there, became fascinated by the place. The result is Detroit: A Biography, a book that makes no pretense of being an exhaustive history, but is, rather, “a book about life, and human nature, and about a city as a living and breathing thing.” And it succeeds at telling the remarkable story of this city’s life, beginning with its “difficult childhood” as a French trading outpost in the early 18th century, its adolescence as a manufacturer of stoves, carriages and rail cars, its brawny adulthood as the center of the world’s automobile industry, and its surprisingly swift decline into decrepit old age. But Martelle, like many smart observers in recent years, does not write Detroit off, nor does he buy into the hackneyed theories about what caused the city to fall so far, so fast -- such tidy scapegoats as the bloody 1967 riot, or the troubled 20-year reign of Mayor Coleman Young. The city’s population peaked in 1950, Martelle notes, the point at which government policies, corporate business practices, and century-old racial animosities began to drain the city of jobs and population. “White flight wasn’t the only force emptying Detroit,” Martelle writes. “During the 1950s the Big Three automakers and other leading industrial concerns embarked on massive decentralization plans to build factories closer to regional customer bases around the country, but also to try to reduce one of the main pressure on profit margins: the cost of labor.” White flight was also greased by aggressive highway building and entrenched (and racist) real-estate policies that benefited the suburbs at the expense of the inner city. In hindsight, there was almost no way for Detroit to fail to fail. This biography ends on a cautiously hopeful note. The Motor City may be gone forever -- “Large-scale industry will not lead whatever comeback might be possible,” Martelle correctly writes -- but he sees signs of hope, including a newly vibrant downtown, many solid neighborhoods, an influx of entrepreneurs, urban farmers, and creative people, a growing sense that Detroit still matters and that it still has a chance. Recent developments indicate Martelle’s optimism might not be misplaced. His book was published in 2011, two years before Detroit became the largest city to declare bankruptcy in American history. The city has just emerged from bankruptcy, far more quickly than expected, and with many valuable assets, including its coveted Institute of Arts, intact. Maybe a new chapter is opening in the life story of this impossibly tortured, impossibly resilient city. A Literary Form In setting out to write the life story of our age’s dominant literary form, Michael Schmidt decided to bypass critics, historians, and, yes, biographers. Instead, The Novel: A Biography is “mainly told by novelists and through novels,” or what Schmidt, echoing Ford Madox Ford, calls “artist practitioners.” The book is staggering -- it covers more than 700 years and runs to more than 1,000 pages. Jonathan Russell Clark tried to grasp the scope of Schmidt’s achievement in an essay here at The Millions, noting that a key to its success is the author’s avoidance of literary theory in favor of a dissection of literary influences. It proves to be a wise choice. And Schmidt, for all his erudition, isn’t shy about injecting his personal opinions, which contribute to this biography’s rumbustious vitality. He prefers David Foster Wallace’s essays to his novels; he disses Samuel Richardson and Michael Crichton; he’s very fond of Virginia Woolf, Hilary Mantel, and Martin Amis; he adores Miguel de Cervantes; and he sticks up for Stephen King. In a nice bit of symmetry, he concludes that the novel is every bit as elastic as the elastic notion of biography that inspired him to write this book. The novel’s great strength, in Schmidt’s view, is its slipperiness, its ability to change shapes, its capacity to absorb material from endless sources, including music, art, history, life, and, of course, other novels. In a final twist, Clark argues in his essay that this biography isn’t a biography after all: “The Novel, I believe, is a novel, the protagonist a murky, somewhat indescribable figure –--the ultimate unreliable narrator -- that Schmidt renders as real and human and flawed as anyone else before him.” An Integer In his anecdotal, entertaining book, Zero: The Biography of a Dangerous Idea, the mathematician Charles Seife describes his subject as “infinity’s twin,” adding that “zero is different from the other numbers. It provides a glimpse of the ineffable and the infinite. This is why it has been feared and hated -- and outlawed.” Ranging over 30,000 years, from the carvings of prehistoric man to the musings of today’s astrophysicists, Seife’s biography notes that Babylonians were using zero 300 years B.C., and Alexander the Great carried zero to India. But the resistance to zero in the West was not overcome until the Renaissance, with the advent of the vanishing point in art, an innovation that could accommodate the twinned concepts of zero and infinity. Since then it has proven useful to everyone from accountants to people trying to envision black holes as stars packed into “zero space.” Seife concludes, “All that scientists know is that the cosmos was spawned from nothing, and will return to the nothing from whence it came. The universe begins and ends with zero.” A worthy subject for a biography, indeed. A Currency Pity the poor almighty dollar. There are 760 billion of them circulating in the world, but two-thirds of them live far from home, in chilly places like the central bank vault in Seoul, South Korea. The dominant global currency since the end of the Second World War, the dollar has recently come under attack, most directly by the European Union’s solid euro and China’s newly muscular yuan, but also by shortsighted policies of the U.S. government. Things have gotten so dire that in his near-future satire, Super Sad True Love Story, Gary Shteyngart has Americans spending nearly worthless “yuan-pegged dollars.” The funny thing about the joke is that it isn’t all that far-fetched. In Biography of the Dollar, his story of the rise and suddenly precarious position of this once-almighty currency, Wall Street Journal reporter Craig Karmin lays out an astonishing fact. Since the United States went off the gold standard in 1971, the dollar’s value has been built on the thinnest of tissues: faith in the idea of America. And we all know how flimsy that is. Karmin notes that the dollar’s historical solidity has done much to lift many global economies. But there is a downside: “Enduring demand for the dollar has also encouraged the United States to run up enormous -- some would say unsustainable -- foreign debts and record deficits.” The U.S., he adds, pays $1 million each day for every man, woman, and child living in the country -- just to service its debt. Which leads Karmin to a scary conclusion: “Too many dollars may be circulating the planet and could be setting the greenback up for a big fall.” Which explains his subtitle: How the Mighty Buck Conquered the World and Why It’s Under Siege. Be afraid. Be very afraid. And you might want to consider buying gold -- or euros or yuan -- while you’re at it. An Animal Writing biographies about non-human subjects, it turns out, is not an invention of our times. Back in the late 19th century, a prolific author, wildlife artist, and environmentalist named Ernest Thompson Seton wrote a delightfully weird novel that purported to reveal the inner life of a grizzly bear. The Biography of a Grizzly tells the story of Wahb, a grizzly cub in western Canada who watches as his mother and three siblings are gunned down by a bad bag of applesauce named Old Colonel Pickett, the cattle king. The orphaned Wahb nurses his own wound and lives a long, lonely, bitter life, so traumatized by the killing of his family that he never takes a mate. Wahb is a sensitive giant, besieged by enemies on every side, as when a beaver trap snaps shut on his paw: “He did not know what it was, but his little green-brown eyes glared with a mixture of pain, fright and fury as he tried to understand his new enemy.” The book was preceded by Seton’s Wild Animals I Have Known, which portrayed wolves and other animals as compassionate individualistic beings. It became one of the bestselling books of its day, part of a wave of books advocating animal rights by featuring anthropomorphic wild animals that had emotions and were capable of learning, teaching, and reasoning. Anna Sewell’s Black Beauty and Jack London’s White Fang were part of the wave, which eventually inspired a backlash by critics who derided such books as “yellow journalism of the woods.” President Theodore Roosevelt, whose love for the outdoors was surpassed only by his love for slaughtering wild animals, weighed in with a magazine article in 2007, dismissing Seton and company as “nature fakers.” Teddy had nerve. A Car Earl Swift published a book this year called Auto Biography, which is, quite literally, the story of the life of a single car -- a 1957 Chevrolet station wagon. Swift, a pit-bull of a reporter, tracked down the man who bought the shiny new car in Norfolk, Va., in 1957, and every one of the dozen people who have owned it since, right up to a bruiser named Tommy Arney who rescued the car from the scrap heap and lovingly restored it to its original glory. The car’s owners, Swift writes, represent “a cross section of America in the late twentieth century and early twenty-first, all of them players in a single narrative for having sat behind the wheel of this Chevy.” Swift’s ingenious narrative strategy reminds me of Marguerite Yourcenar’s in her novel A Coin In Nine Hands, which follows the journey of a 10-lira coin as it passes through the hands of nine very different people on a single day in Rome in 1933. These nine people, like the dozen owners of the '57 Chevy, are linked in ways they cannot explain or understand. But in the hands of a gifted writer, just about anything -- a car, a coin, a ring, a book, a smell, a memory -- can be an opening into the mysteries of human connectivity. In closing -- and in the interest of full disclosure -- I should tell you that my interest in the elastic nature of biography dates back more than 20 years. In the early 1990s, I was driving a luscious lipstick-red and black 1954 Buick Special, a car that became my Muse and a central character in my first novel, which told the story of a fictional publicity campaign built around the sale of the 500,000th Buick in 1954, when Buick and rival Plymouth were locked in an actual sales war for the number three slot behind Chevy and Ford. Since the novel’s arc followed that particular Buick from conception to birth to infancy -- from the drawing board to the assembly line to the showroom to the first buyer’s driveway and finally onto a magazine cover -- I came to think of the novel as the life story of the car. And so my working title was Biography of a Buick. As publication neared, my editor contacted Buick’s PR people in Detroit, hoping they might somehow help us promote the book. Instead they bristled, threatening legal action if a General Motors brand name appeared in the title. My editor had no desire to go up against GM’s legal department, and so he persuaded me, kicking and screaming, to change the title to Motor City. With time I’ve grown to like the title, maybe because I ended up getting a consolation prize. The novel also sold in Great Britain and Germany, and my publishers there, unfazed by the huffing of GM’s legal department, stuck with my original title. So the book came out in England as Biography of a Buick and in Germany as Biographie eines Buick. I got to have it both ways, and the life story of my car was destined to have a life of its own.