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Ronald Reagan and Jimmy Carter both claimed to have seen flying saucers. Reagan also told the prime minister of Israel that he had been present at the liberation of the Nazi death camps, although his duties in the army film unit never took him out of California. Like a reported 48% of Wall Street investors, the president always consulted his astrologer before taking an important decision. The taste for horoscopes is not confined to Republicans. John F Kennedy’s favourite editor, Ben Bradlee of the Washington Post, and his wife Sally Quinn, the paper’s famous style correspondent, were private clients of the Post’s resident astrologer, the superbly named Svetlana Godilla.

Nor is it only the Americans who are suckers for the occult. Glenn Hoddle, when he was England’s football coach, memorably declared that disabled people were paying off the bad karma they had collected in previous incarnations. Tony Blair took a dim view of this, demanding (and obtaining) Hoddle’s resignation. But were Hoddle’s views any weirder than Cherie Blair inviting a feng-shui expert to rearrange the furniture at Number 10, and wearing a magic pendant known as the BioElectric Shield that surrounded the wearer with a cocoon of energy to ward off evil forces?

Mrs Blair’s Catholic faith was broad enough, it seems, to accommodate new-age spirituality in all its exuberant variety. G K Chesterton is supposed to have said that “when a man ceases to believe in God he does not believe in nothing; he believes in anything”. But these days religion seems to be an optional extra rather than an alternative. Like Lewis Carroll’s White Queen, many of us take pride in believing as many as six impossible things before breakfast.

Francis Wheen takes a hugely enjoyable sweep through the tangled thickets of superstition and gullibility in which modern man likes to ramble. He takes particular delight in reminding us how easily fools are parted from their money and how many of them there are. The 1980s were a golden age for the fraudster, a time in which, as the management theorist Peter Drucker remarked, “people use the word ‘guru’ only because ‘charlatan’ is too long”. It was the egregious arbitrageur Ivan Boesky who coined the immortal reassurance that “greed is healthy. You can be greedy and still feel good about yourself”. He finished up in the slammer, along with Michael Milken, the junk-bond king, and quite a few of those other entrepreneurs tipped for stardom in such books as The Risk-Takers.

It was an age of ominous prophecies, such as the so-called Jupiter Effect, which claimed that on March 10, 1982, when the moon was in the seventh house and Jupiter was aligned with Mars, Los Angeles would infallibly be destroyed. A stream of Californian householders headed for the hills, with the more callous of them renting out their houses for the month. Better still was the Daily Mail’s claim on Saturday, August 31, 1997 that Monday ’s issue would explain how all the main events in world history were encoded in the Bible. Unfortunately, the one event not thus encoded was the one that happened that Saturday night — the death of Princess Diana.

Wheen claims that “by the end of the 20th century there were countless indications of a general retreat from reason”. But delightful reading though it is, the book does not explain why we should be any more irrational and gullible than previous generations — if indeed we are. After all, Wheen argues quite rightly that one of the ways we are so idiotic is that we refuse to learn from the catastrophic mistakes of our ancestors, even when they have been pointed out to us, for example in countless retellings of the South Sea Bubble and the Wall Street Crash.

He dates the arrival of the new Dark Ages to 1979, the year in which Margaret Thatcher and the Ayatollah Khomeini came to power. But he admits himself that Thatcher was only trying to revive the teachings of Adam Smith, a giant in that 18th-century Enlightenment Wheen so admires. And I didn’t notice much enlightenment shining on the Islamic world before Khomeini appeared on the scene.

There is also a more unnerving question that Wheen does not address at all. Belief in weird systems and dodgy diviners does not of itself appear to disqualify the believers from achieving quite useful things. Mrs Blair is a first-rate and hardheaded human-rights lawyer. Sir Isaac Newton spent as much time on his alchemical and apocalyptic speculations as he did on what we call science. W B Yeats lapped up all the occult mumbo-jumbo he could find, but no poet has written with more desolate clarity about the corrupting effects of political violence.

And some prophecies do come true. Who said in 1983, “I believe that Communism is another sad, bizarre chapter in human history whose last pages are even now being written”? Why, poor old crackbrained Ronnie Reagan, and Wheen quotes him saying it. Yet I cannot think of another politician anywhere who dared to make such a prophecy.

Perhaps the imagination does need to wander off-beam now and then if it is to pick up fresh vibrations. If you stay on the trolley, all you see are the tramlines. Or to put it in oldspeak, when Horatio says, rather ploddingly, that the sight of Hamlet’s father’s ghost is “wondrous strange”, Hamlet tells him “And therefore as a stranger give it welcome.”

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