So even the ghostwriter had a ghostwriter: Bob Hostetler, an evangelical pastor and author from Ohio, rewrote many passages, especially in the section that narrates Flew’s childhood. With three authors, how much Flew was left in the book? “He went through everything, was happy with everything,” Varghese said.

Cynthia DiTiberio, the editor who acquired “There Is a God” for HarperOne, told me that Hostetler’s work was limited; she called him “an extensive copy editor.” “He did the kind of thing I would have done if I had the time,” DiTiberio said, “but editors don’t get any editing done in the office; we have to do that in our own time.”

I then asked DiTiberio if it was ethical to publish a book under Flew’s name that cites sources Flew doesn’t know well enough to discuss. “I see your struggle and confusion,” she said, but she maintained that the book is an accurate presentation of Flew’s views. “I don’t think Tony would have allowed us to put in anything he was not comfortable with or familiar with,” she said. “I mean, it is hard to tell at this point how much is him getting older. In my communications with him, there are times you have to say things a couple times. I’m not sure what that is. I wish I could tell you more. . . We were hindered by the fact that he is older, but it would do the world a disservice not to have the book out there, regardless of how it was made.”

MANY AUTHORS DON'T WRITE their own books. Some don’t even read them: sports fans will remember when the basketball player Charles Barkley complained that he was misquoted in his own autobiography. It could be that two years ago, when Varghese started writing Flew’s book, Flew was a fuller partner in the process than he remembers (the section on Flew’s childhood could hardly have been written without his cooperation). And perhaps he was recently reading those philosophers whose names he now does not recognize. Two years ago, he might have had a fruitful conversation with Brian Leftow, a man he does not remember. Two years ago, he and Gary Habermas might indeed have been good friends.

But it seems somewhat more likely that Flew, having been intellectually chaperoned by Roy Varghese for 20 years, simply trusted him to write something responsible. Varghese had done him so many kindnesses. He introduced Flew to Gerald Schroeder and John Haldane, and, I learned, he flew to England to chauffeur Flew to meetings with Leftow and the Christian philosopher Richard Swinburne (although when Leftow and Swinburne appear in the book, the conversations are described as if Varghese were not present). Varghese also gave Flew adventures, jetting him to Dallas and New York, putting him in a DVD documentary, getting his name in the papers. If at times Flew could be persuaded, by a letter or a phone call from an American atheist, that Varghese and his crew were not the eminent authorities on science they made themselves out to be, he was always happy to change his mind back. These Christians were kind and attentive, and they always seemed to have the latest research.

To believe that Flew has been exploited is not to conclude that his exploiters acted with malice. If Flew in his dotage was a bit gullible, Varghese had a gullibility of his own. An autodidact with no academic credentials, Varghese was clearly thrilled to be taken seriously by an Oxford-trained philosopher; it may never have occurred to him that so educated a mind could be in decline. Habermas, too, speaks of Flew with a genuine reverence and seems proud of the friendship.

Intellectuals, even more than the rest of us, like to believe that they reach conclusions solely through study and reflection. But like the rest of us, they sometimes choose their opinions to suit their friends rather than the other way around. Which means that Flew is likely to remain a theist, for just as the Christians drew him close, the atheists gave him up for lost. “He once was a great philosopher,” Richard Dawkins, the Oxford biologist and author of “The God Delusion,” told a Virginia audience last year. “It’s very sad.” Paul Kurtz of Prometheus Books says he thinks Flew is being exploited. “They’re misusing him,” Kurtz says, referring to the Christians. “They’re worried about atheists, and they’re trying to find an atheist to be on their side.”

They found one, and with less difficulty than atheists would have guessed. From the start, the believers’ affection for Antony Flew was not unrequited. When Flew met Christians who claimed to have new, scientific proof of the existence of God, he quickly became again the young graduate student who embarked on a study of the paranormal when all his colleagues were committed to strict rationalism. He may, too, have connected with the child who was raised in his parents’ warm, faithful Methodism. Flew’s colleagues will wonder how he could sign a petition to the prime minister in favor of intelligent design, but it becomes more understandable if the signatory never hated religious belief the way many philosophers do and if he never hated religious people in the least. At a time when belief in God is more polarizing than it has been in years, when all believers are being blamed for religion’s worst excesses, Antony Flew has quietly switched sides, just following the evidence as it has been explained to him, blissfully unaware of what others have at stake.