"The biggest misfortune in human history is the invention of the combustion engine. Cars and airplanes diminish the world, rob it of all its diversity. Young men who meet me want to know how they could do what I've done. But all they can be is tourists now."

So says Wilfred Thesiger, the man generally regarded as the greatest living explorer, and author of what is arguably the best modern travel book, Arabian Sands. Thesiger lives in a suburb of London now, in a pleasant retirement home far from the fierce and alluring desert he depicted nearly a half-century ago in that book. He was one of the first Westerners to cross the half-million square miles of the Empty Quarter; in doing so, he not only witnessed but became part of a timeless way of nomadic life just before it changed utterly.

"In the desert," he wrote, "I had found a freedom unattainable in civilization; a life unhampered by possessions, since everything that was not a necessity was an encumbrance . . . I had learnt the satisfaction which comes from hardship and the pleasure which derives from abstinence; the contentment of a full belly; the richness of meat; the taste of clean water; the ecstasy of surrender when the craving for sleep becomes a torment; the warmth of a fire in the chill of dawn."

It was life stripped down to its essentials, with no cell phone to bring in a helicopter if he should fail -- and little to mark achievement when he succeeded.

"To others," he wrote of his first trek across the desert, "my journey would have little importance. It would produce nothing except a rather inaccurate map which no one was ever likely to use. It was a personal experience, and the reward had been a drink of clean, nearly tasteless water. I was content with that."

It's this investigation of the real point of traveling that renders Arabian Sands peculiarly up-to-date. If anyone with an ample bank account can make it up Everest, is it realistic to have a concept of adventure anymore? If there's nowhere left to go, is there any reason to go anywhere? Or is it all just tourism now?

Thesiger thinks so, counting himself "fantastically lucky" to have been able to do what he did in a time when the world wasn't overrun by Benettons and McDonald's. After his Arabian years, he spent some time in southern Iraq, an experience that produced his second classic, The Marsh Arabs -- another tribute to a way of life that has been utterly extinguished. He also did a lot of wandering in Ethiopia, Sudan and Kenya, as well as in the mountains of Asia.

Until very recently, he notes, most such places "had no contact with Western civilization. Now, you go to most of them and I suppose they have, what's the damn thing called?"

The Internet?

"No, television. Thank God I'm 88."

The View From 88

And not, say, 40. "I cannot picture myself wanting to climb space. I have no interest at all in landing on Mars." He dismisses the alternative, exploring under the sea, with the wave of a hand. "I don't know what I'd do. Go to Mongolia. See if I could settle down with the Mongols, with their horses."

Mongolia, he's told, is pretty well Westernized now.

"Then I'd leave them behind."

A maid brings in tea. "I resent every material manifestation of our modern civilization," the writer says, pouring me a cup. "I think we'd have been infinitely happier if we still depended on walking and going about with horses. Sugar?"

From anyone else, this would be easily dismissed as romanticism. The life of pre-modern man was generally short and brutal, especially if you didn't happen to be white. But then, Thesiger has always reveled in a certain form of brutality.

He was a hunter since he was a tot, and a warrior when fighting the Germans. In his autobiography, he writes that the desert Arabs "had little veneration for human life. In their frequent raids and counter-raids they killed and were killed, and each killing involved the tribe or family in another blood-feud to be settled without mercy -- though in no circumstances would they have tortured anyone. I soon acquired the same attitude."

As a young man, he spent time in the Danakil region of what is now Ethiopia. This was rough country. "The only thing that matters in a Danakil's life was the number of men he had killed and castrated," he told me. "And you could tell by looking at him how many he had killed -- he hung down these strips of leather. I remember seeing an old man -- this is a vivid memory of mine -- and thinking, `Good God, he's only killed two.' "

Did this make him less of a man?

"Well, it certainly made him less of a Danakil."

Some commentators, like Ian Buruma in the New York Review of Books, have taken Thesiger to task for so whole-heartedly praising this sort of savagery. "What Thesiger admires in his tribal comrades is not simply their colorful customs and friendly disposition, but their worship of physical power," the critic wrote. "Thesiger is in love with racial macho."

"It depends on what you call barbarism," the explorer replies. "It's obviously barbaric to have a life based on killing and castrating other people. But I got along quite well with the Danakil." He adds that they were "constantly in danger of attack, so none of them were ever bored. I wasn't either."

What redeems him is a certain stylishness, a sense that he has strolled straight out of a boy's adventure book from the turn of the century or, in a more modern reference, that he's a real-life Indiana Jones. Eric Newby, no mean traveler himself, recounted in his own classic narrative, A Short Walk in the Hindu Kush, meeting Thesiger in the Himalayan foothills. Suffering from dysentery, Newby's party was cranky and tired.

Up strides Thesiger, wearing "an old tweed jacket of the sort worn by Eton boys, a pair of thin gray cotton trousers, rope-soled Persian slippers and a woollen cap comforter." Not exactly your usual mountain-climbing attire.

"England's going to pot," Thesiger says. "Look at this shirt, I've only had it for three years, now it's splitting. Same with tailors; Gull and Croke made me a pair of whipcord trousers to go to the Atlas Mountains. Sixteen guineas -- wore a hole in them in a fortnight. Bought half a dozen shotguns to give to my headmen, well-known make, twenty guineas apiece, absolute rubbish."

The ground, Newby writes, was like iron with sharp rocks sticking up out of it. Preparing for bed, he and his companions started to blow up air mattresses. Thesiger was appalled. "God," he said, "you must be a couple of pansies."

Cookies accompany our tea, but he eats none of them. They're a luxury of civilization, perhaps, fit only to be spurned. He tells me to have them instead. I do, realizing this marks me as a pansy.

But then in Thesiger's world, there's no hope for anyone. "It's inconceivable there will be human beings on the planet a century from now. Something will go out of control. They may have invented some germ they suddenly find is absolutely deadly." He states this without satisfaction, merely a grim resignation.

The Last Itinerary

This is an old age home, not a nursing home. Two homes, in fact, facing each other across a small patch of lawn in Purley, an outlying suburb of London. The common rooms are large and airy, giving a relaxed, clubby feel. Thesiger's own chamber is small but with distinctive touches that are probably lacking in his neighbors'.

There's a knife on the dresser, for instance, so big as to be practically a scimitar. "The chiefs in the Congo gave it to my father," the explorer explains. "He was there at the end of the last century, sent out by the Foreign Office to investigate reports of Belgian atrocities. He got on good terms with the locals and was presented with the knife. It keeps me company."

Having good relations with the locals is a family tradition. Thesiger went one step further than his father and essentially became a native. "When I went to the desert, I was prepared to meet the challenge on equal terms," he says. "I found I could do that, but where I fell short was in patterns of behavior."

Once, he and his nomadic companions were fortunate enough to catch a hare. It had been more than a month since they had eaten meat, and so they promptly made a stew and began to salivate. Unfortunately, three friends wandered by just as dinner was being served, and tradition dictated that they get the food instead. Thesiger reports that he felt murderous. "That's where I fell down," he says. "But even so, they accepted me."

Against one wall of his room, there are several shelves of books; most of them are multiple editions of Thesiger's eight titles. While he was doing his own adventuring, he had room in his baggage for only a spare volume or two, which tended to be the classics. "The two books I carried most of the time," he says, "were Kim and Lord Jim." Conrad and Kipling were fitting, surely, but I like even more Newby's observation that he saw in Thesiger's kit the first volume of Proust, in French. Lavish French fiction about subtle matters of psychology -- just the thing after a day romping at high altitudes and a dinner of, at best, a scrawny chicken.

All that's gone now, including the pleasures of prose. "I find it impossible to read for any length of time. Two or three pages and my eyes have had enough."

He estimates he's walked 100,000 miles in his life, during which his eyes saw some amazing things. He was the first Westerner to gaze on the quicksands of Umm al Samin, always described as "fabled."

They could walk only on the edges, he wrote in Arabian Sands: "Often our weight broke through the surface crust of salt, and then we waded through black clinging mud which stung the cuts and scratches on our legs. Incessantly the half-bogged camels tried to stop, but we dragged and beat them forward, fearful lest, if they ceased to move, they would sink in too deep to get out again."

His walking is now done with the help of a cane. "In another two years, unless I'm lucky and already gone, I'll be carried about in a wheelchair."

When I saw him, it was only his second day in this room, with its copy of the London Times on top of the bed and his slippers tucked underneath. Before that, he had been down the hall, in a room with no view at all. That was intolerable even for a stoic.

"It was rather like being locked up in a cell," he says. Now, with his window, he's content. He'd rather be in Kenya, where he lived for the last 30 years, or almost anywhere else, really. But he's not, so he'll persevere. "I've accepted that this is going to be my resting place. There is no alternative."

CAPTION: Wilfred Thesiger in 1949