The New York Times Magazine

Neil Heffernan was listening to his fiancée, Cristina Lindquist, tutor one of her students in mathematics when he had an idea. Heffernan was a graduate student in computer science, and by this point — the summer of 1997 — he had been working for two years with researchers at Carnegie Mellon University on developing computer software to help students improve their skills. But he had come to believe that the programs did little to assist their users. They were built on elaborate theories of the student mind — attempts to simulate the learning brain.

Amwell Township is a 44-square-mile plot of steep ravines and grassy pasturelands planted with alfalfa, trefoil and timothy in the southwestern corner of Pennsylvania. It’s home to some 4,000 people, most of whom live in villages named Amity, Lone Pine and Prosperity.

As chief medical and scientific officer of the American Cancer Society, Otis Webb Brawley — who is also a professor of oncology and epidemiology at Emory University — is the public face of the cancer establishment. He operates in a world of similarly high-achieving, multiple-credentialed, respectable professionals, where insults tend to be delivered, stiletto-style, in scientific language that lay people aren’t meant to understand.

Oilmen are optimists, by creed if not always by nature, and early last spring things looked, as those in the industry like to say, prospective. The deepwater rigs in the Gulf of Mexico were steadily drilling, with no suggestion of any impending calamity, and oil was flowing from the vast finds in offshore Brazil. Circumstances looked particularly prospective to a geophysicist named Jim Farnsworth, who works for Cobalt International Energy, a company that held a group of leases 50 miles from the mouth of Angola’s Cuanza River basin.

A shopkeeper in Italy placed an order with a Chinese sneaker factory in Putian for 3,000 pairs of white Nike Tiempo indoor soccer shoes. It was early February, and the shopkeeper wanted the Tiempos pronto. Neither he nor Lin, the factory manager, were authorized to make Nikes. They would have no blueprints or instructions to follow. But Lin didn’t mind. He was used to working from scratch.

Two carloads of gunmen wearing ski masks parked outside Goodfellas, a popular karaoke bar in the Nigerian city of Port Harcourt, on a damp August night in 2006. When the first militant barged through the front door, he was holding an automatic rifle and yelling, “Everybody down!” John, a gregarious Scottish oilman, was sitting at a round table near the entrance, watching one of the owners, another Scot, impersonate Mick Jagger while singing “Satisfaction” at the karaoke machine. He and the other 50 or so bar patrons dove for cover.

Once a month a tractor-trailer rolls up to the Family Early Learning Center, a one-room preschool in East San Jose, Calif., that doubles as a food pantry for poor families with young kids. On a bright Friday in August, a dozen or so women from the neighborhood gathered for the truck's arrival. Volunteers as well as customers, they had come to help unload the monthly delivery of groceries from the local food bank.

Interview by DEBORAH SOLOMON

"The Evolution of God," your new book on the history of religion, strikes me as a welcome antidote to the stream of books by atheists that have become best sellers in recent years. Doesn't it seem as if atheism has become its own form of fundamentalism?

One recent evening at the presidential palace in Malé, the capital of the Maldives, around 100 people showed up to watch a movie. Rows of overstuffed chairs in a gaudy combination of stripes and paisleys faced a projection screen hanging on the front wall of what seemed like a grand ballroom. At the back of the hall, journalists erected camera and microphone rigs: Mohamed Nasheed, the Maldives’ 41-year-old president, was expected to make a major announcement after the film.

In the months after 9/11, American forces in Afghanistan bombed the Taliban and, in vain, hunted for Osama bin Laden, while in Washington counterterrorism experts worried about "the next Afghanistan," a safe haven where terrorists would train, test their weapons and organize attacks on the United States. These discussions produced a double-barreled national-security strategy that dominated President George W. Bush's tenure. The first element of the strategy was to identify and eliminate terrorist networks that already existed.