The delusions of crowds Why people go mad in groups

God, greed, and the yen for conformity reliably override reason, according to this sweeping survey of religious and financial manias. Neurologist and historian Bernstein (A Splendid Exchange) shares vivid accounts of several centuries of sectarian crazies, from the Anabaptists who took over the German city of Münster in 1534, imposing communism and polygamy and executing dissenters, to Branch Davidian messiah David Koresh and the Islamic State. On the finance front, he recaps the South Sea bubble in 18th-century England, the 1990s tech bubble, and other stock market frenzies. Bernstein lucidly deploys neurobiology, behavioral economics, and social psychology to explain why reason fails and other instances, noting, for example, that many people will believe two obviously unequal line segments to be the same length if other people say they are. Unfortunately, his conflation of all irrational doctrine with madness makes him sound somewhat hysterical about even mainstream religious politics: the "dangerous" end-times beliefs of American evangelical conservatives could, he suggests, "incinerate a large portion of humanity" by facilitating nuclear war. The result is an entertaining and insightful analysis of delusional outbursts that occasionally goes too far. Photos. (Feb.)

An intriguing contemporary update of Charles Mackay's 1841 classic, Memoirs of Extraordinary Popular Delusions. Neurologist and journalist Bernstein effectively explains the biological, evolutionary, and psychological bases of human irrationality. "When presented with facts and data that contradict our deeply held beliefs, we generally do not reconsider and alter those beliefs appropriately," he writes. "More often than not we avoid contrary facts and data, and when we cannot avoid them, our erroneous assessments will occasionally even harden, and, yet more amazingly, make us more likely to proselytize them." Asked about the safety of vaccines during the 2016 presidential campaign, neurosurgeon Ben Carson summarized the overwhelming evidence in favor. Donald Trump disagreed, describing a "beautiful child" who became autistic after a vaccination. Sadly, "most observers scored the interchange in Trump's favor." Readers will wince at the often bloody hysteria that accompanied the Reformation, roll their eyes at our inability to resist get-rich-quick schemes, and chuckle at the widespread American movement that awaited the world's end in 1843--all of which makes for disturbing yet fascinating reading. The rise of evangelicalism is arguably the most important transformation in recent American political life, and many readers may be shocked that 35% of Americans believe "Jesus will return to earth in their lifetimes." Citing the work of religious historian Robert Wright, Bernstein notes, "Revelation's opacity and ambiguity only amplified its influence, since they open the way to a wide range of allegorical interpretations about when and how the world ends." Furthermore, this belief is "so embedded in our political system that at least one U.S. president, Ronald Reagan, subscribed to it, as do a large swatch of politicians at all levels," including Mike Pence. The author offers solid sections on digital age hucksters before a concluding chapter on Muslim apocalypticists, who have much in common with the Christian variety. Bernstein's account of financial shenanigans is a jolly ride, but he finds no humor in religious extremism, and readers may share his despair at learning what seemingly educated people believe. A well-researched, wide-ranging, and discouraging addition to the why-people-do-stupid-things genre. Copyright (c) Kirkus Reviews, used with permission.