It was the dream of a lifetime for George O'Leary: A chance to coach the world's most prestigious football team—Notre Dame's Fighting Irish. But the dream soon became a nightmare.

The day after he signed his contract with Notre Dame, O'Leary's résumé was sent to the press—a résumé that included "inaccuracies" about his education and college football letters. A few days later, O'Leary resigned in disgrace, the victim of his own long-ago lies.

It's the latest example of what's become an epidemic of lying.

In recent years, politicians and pundits, professors and even Pulitzer Prize-winners have been caught dealing in deceit. One of the nation's most respected historians, Stephen Ambrose, plagiarized portions of other historians' works and—notwithstanding his public apology—seemed hardly disturbed by the resulting controversy.

Historian Joseph Ellis, who won the Pulitzer Prize for his book, Founding Brothers, was caught inventing a Vietnam War record for himself. So was Tim Johnson, manager of the Toronto Blue Jays. Ex-conservative writer David Brock admitted he'd made up sordid details about Anita Hill. Gloria Steinem's claim about the number of women who die of eating disorders—supposedly 150,000 a year—turned out to be a huge feminist hoax. James Patterson and Peter Kim, authors of The Day America Told the Truth, estimate that 91 percent of us regularly embroider the truth. "We lie and don't even think about it," Patterson and Kim write.

Why has lying become so much more prevalent? Some scholars believe the problem arose out of the gradual adoption of a utilitarian ethic—one that began eroding the traditional Christian ethic in the West in the middle to late 19th century. This ethic says the (good) end justifies the means—that ...