Midway through our conversation about Fresh Air Fiend, Paul Theroux reminds me that during the 15 years in which he wrote the 49 travel essays and articles collected here, he also wrote a major book on China (Riding the Iron Rooster), three additional travel books, a controversial memoir about his friendship with V.S. Naipaul (In Sir Vidia’s Shadow), and more than a handful of novels (including My Secret History, Millroy the Magician, and Kowloon Tong). Something like a dozen books in all.

"It’s not that I was writing these pieces with my left hand," Theroux says, "but I was doing other things at the same time. These pieces illuminate those books, and those books derive somewhat from the experiences recorded here. There’s a certain synchronicity in writing travel pieces and also living my life as a novelist and a travel writer."

This is disheartening. You’d expect—perhaps even hope—that there’d be a significant decline in quality in these occasional pieces, written over the years for publications as varied as Outside magazine, The New York Times, Vogue, and Vanity Fair. And, no doubt, readers will have their favorites and less favorites among them. But in each of the pieces collected in Fresh Air Fiend, the immensely satisfying interplay of observation, wit, and insight (as well as a certain disquieting undertone) that we’ve come to expect from Paul Theroux is very much in evidence.

The essays and articles themselves range through time and across five continents. In the book’s first section, called "Time Travel," Theroux reflects on memory, creativity, and turning 50 and writes about the job of the travel writer. Later, in the book’s title essay, he explains his need for solitary exercise—bicycling, kayaking, sailing—to assuage "the loneliness of the long-distance writer." He spends a solitary week in the Maine woods in wintertime. He travels down the Zambezi River, and down the Yangtze. He writes of meeting Gerard d’Aboville, who rowed across the Pacific Ocean alone in a small boat in 1993. He kayaks in the Philippines and visits Hong Kong on the eve of the hand-over to China.

By my lights, the most interesting pieces in this collection are Theroux’s essays on books of travel. His introductions to reissues of his own books are shapely vignettes from a writer’s autobiography. His essays on the books of other writers — a surprising selection that includes Henry David Thoreau’s Cape Cod, Robinson Crusoe, and Apsley Cherry-Garrard’s memoir of the 1910-1913 Antarctic expedition, The Worst Journey in the World—will add volumes to the avid reader’s ever-growing pile.

"I can’t imagine ever being on a trip and not having something to read," Theroux says. "To me that would be a disaster." And what he reads while traveling becomes part of the background of his essays and articles.

Thus, in his piece on camping in the Maine woods, he mentions rereading Madame Bovary by flashlight. On a trip to London to promote one of his books, he reads F. Scott Fitzgerald’s Tender is the Night. In Amsterdam he reads Henry James’s The Aspern Papers.

"In terms of selection, I take paperbacks that I happen to be reading at the time and ones that I have intended to read," Theroux says. "I’m an omnivorous reader, and if you read a lot, you always have a kind of reading program going, a sort of private scholarship. I have to know the interior of books. And I’m very interested in writers’s lives — what they’re doing at particular stages of their lives, what they’re writing. I recently realized that there were a number of Henry James stories that I hadn’t read. So I started to read all the stories that James wrote when he was around my age, from his early to his late 50s, the years he regarded as his middle years. He had a sort of nervous breakdown then. A lot of those stories are about an older, very James-like writer and a younger writer."

Guide books seem singularly lacking in Theroux’s reading program, probably because he sees a wide gulf between tourism and travel. "There really is an enormous difference between travel in its classic sense and tourism," he says. "Tourism—sightseeing—is expected to be fun. You do it in large groups, it’s very companionable, it’s comfortable, and it’s very pleasant. Travel has to do with discovery, difficulty, and inconvenience. It doesn’t always pay off. There’s a strong element of risk in travel. Time is usually not a constraint for the traveler, but every tourist is under a time constraint. The traveler doesn’t really know where he or she is going, but has a sense of discovery. Tourists know exactly what they want to see and they arrive with a lot of preconceived notions. There’s a kind of enlightenment in classic travel which has nothing to do with materialism or consumerism. By its very nature, travel is cheaper."

A recurrent theme in these essays is that the traveler must approach the world with humility. "If you’re arrogant, you miss a lot," Theroux says.

He adds, "You have to realize that you are just a traveler; you are not home. You need the people you meet. You need their protection. You need their good will. You can’t be presumptuous. You see all sorts of people traveling. There are some amazingly arrogant people who think that because they are American, for example, they can collect hospitality just because they come from a wonderful country that has been very generous. They are sometimes surprised that people don’t give them the respect they think they deserve. If you’re smart, you’ll be very polite, you’ll develop good manners."

According to Theroux, the travel writer—or any writer, for that matter—has the added obligation of telling the truth. His or her truth, that is, since Theroux also notes that every traveler’s journey is different.

Theroux has occasionally taken some heat for his sort of truthtelling. His essay on his friend and fellow travel-writer Bruce Chatwin (1940-1989), which is included in this volume, offended the bearers of the Chatwin flame—until corroborated by a recent biography. His book Riding the Iron Rooster was judged by some to be too harsh on China—until Tiannamen Square. His memoir about V.S. Naipaul continues to stir controversy.

"I have discovered," Theroux says, "that if you tell the truth, you are describing the future. There’s something prophetic about the truth. When you see it and describe it—without stereotypes and preconceptions, but with subtlety—a book can seem like prophecy. So I have no problem telling the truth. But I have a great problem with being untruthful. As my father used to say, ‘You can watch a thief, but you can’t watch a liar.’ "

Can it really be so simple? "It’s sometimes unbelievably difficult," Theroux says. "It’s the reason why it’s probably impossible for me to hold a job writing. I couldn’t work for a newspaper or a magazine or as a copy editor. I could be hired to write my own piece, but I can’t be hired to write someone else’s piece. Telling the truth can make you unemployable. But a writer is basically an unemployed person anyway. It’s something that you just have to live with."

Alden Mudge works for the California Council for the Humanities.