History shows that cataclysmic events are often followed by rumor. Out of the thick black smoke rising over Pearl Harbor some 60 years ago came a separate plume just as dark: hearsay and rumor. Like the one about an imminent attack on the coast of California by Japanese bombers and subs. Of course, there wasn't one.
Or the hundreds of rumors that surfaced during those troubling months after JFK's assassination - where a grassy knoll in Dallas became fertile ground for more than just grass.
And, of course, there are still plenty who believe Elvis just ducked out of public view for while.
In the wake of Sept. 11, we asked a group of students at Northwestern University what they had had heard.
Jonathon Carter: "Osama bin laden gets his funding from a cola additive that's produced in Sudan."
Annie Johnson: "Garlic and oil and oregano are effective substitutes for anthrax antibiotics."
Manu Krishman: "Ryder trucks and U-haul trucks have been missing from their depots and they're going to be used eventually at various targets around the U.S."
David Emmery spends his day debunking urban legends like those on his Web site at About.com.
"I've never seen such a volume of rumors," he says. "I've never received so much e-mail -- people asking me so many questions about things they've heard, and want to know if they were true or false."
And since Sept. 11, he's seen an unsettling evolution.
"The earliest rumors had mostly to do with coping with the tragedy, trying to deal with it, and trying to explain it."
Like the rumor that Nostradamus had foretold the events of Sept. 11: "In the City of God there will be a great thunder Two brothers torn apart by Chaos." (Nostradamus died in 1566.)
Then there was the miracle about the man who survived the tower attack by surfing down 86 stories of debris.
It never happened.
Or how about the rumor that NASA asked people to stand outside with a candle - so a satellite could snap a picture of a nation in mourning.
Aaron Dibner Dunlap thought it was a great idea. He found out the next day, it wasn't true either. He says, "I spread it, and our dorm actually did that. And I thought, so what if it's false? Still, it's a unifying thing."
But that unity has turned to something else. According to Emmery, "As this crisis has progressed, and as we've begun to take military action, as the threat seems to have persisted, the rumors are becoming more and more about fear."
One the most persistent: an eerie rumor about Halloween. As it's told, a women received an ominous note from her Afghani boyfriend, begging her "not to get on any commercial airlines on 9/11" and "not to go to any malls on Halloween."
Just another falsehood so many of us bought into. But why? We turned to a rumor expert, Gay Fine, a professor at Northwestern. "In a situation like this," he explains, "the key factor is to make sense out of ambiguity."
And there is a lot of ambiguity these days.
"People have a strong, powerful need to know what is happening," says Fine. "And when the situation is ambiguous, uncertain, people are concerned, when it's important, that's when you'll see rumors."
The owner of a gas station outside Chicago found that out the hard way. Irshad Kahn was born and raised in Chicago, a Bears fan through and through.
Recalls Kahn, "I've always heard rumors spread like fire, but I mean, this proved it to me right there."
Just days after the attacks, a rumor began to bubble that he had put up a poster of Osama bin Laden. In truth, the only thing he had posted, was an American flag. The only picture of bin Laden was in the newspapers he sells.
But the rumor spread so fast, his business dropped by 50 percent, and he started getting hate mail and threatening phone calls.
"I've worked really hard to build this business up to where it was at. And to see rumors finish my business off in that aspect, I'm sure there's small percentage, even if there is, that won't come in here anymore."
But if you think rumors spread fast in a big city like Chicago -- try coming to a small town like Ephrata, Pa., where there are just as many people as there are fence posts to talk over.
And, suddenly, the two Egyptian brothers, who have run the local diner there for the last six years, were suddenly the embodiment of al-Qaida in Ephrata.
One rumor had them traveling to New York every Tuesday - EXCEPT Sept. 11. Another talked of a swarm of black Suburbans - agents rushing into the diner to arrest them both - prompting an inquiry from the local newspaper.
Business dropped off so fast that Osama Monsour (who incidentally goes by Sam) and his brother Mohamed (who goes by Mike) actually considering packing it in for good.
Says Mike Monsour, "I was telling my wife, let's go home, there's nothing for me here I was almost letting some of my employees go. I was going to let them go, some of them, because I couldn't afford to pay them."
Eventually, the sun rose again on the Sunset Diner - thanks to the help of a few good-hearted neighbors who beat the rumors down.
Back in Chicago, Kahn is taking his case to court, suing at least one person he knows who helped spread the rumor about him.
Still there are some rumors that seem almost immortal. Like that pesky one about Halloween and shopping malls. It, too, will eventually die, but only after fulfilling its mission. It's a safe bet that 90 percent of the people who heard the rumor probably aren't going to go to a mall on Halloween, just in case.
"That's right," says Fine, "because they'll say, 'What's the cost? Why not? Maybe the chance is one in a million, but it's a chance I can easily avoid.' And so the malls will be empty."
Says Annie Johnson, a Northwesterstudent, "I don't think I fully believe them, but I keep them in the back of my head. I'm not going in a mall on Halloween. I don't care whether or not I believe it."
After all, when the impossible to believe happens, it becomes that much easier to believe the improbable.
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