If you believe that the 1969 Apollo moon landing was staged in Hollywood, that Marilyn Monroe was killed by the Kennedy family and Lady Diana by the royal family ...
If you believe that FDR allowed the Japanese to attack Pearl Harbor to facilitate America's entry into World War II and that the Bush administration brought down the twin towers with explosive charges and holograms in order to provoke a war for oil ...
If you believe that President Barack Obama was born in Kenya and educated in a madrassa and is rushing through health-care reform because he knows he is about to be discovered as an Islamic terrorist mole ...
If you believe that Jesus and Mary Magdalene were married and their descendant is a woman living in Paris, welcome to Michelle Obama's vegetable garden, where the cabbage heads are human.
In June, Mother Jones magazine wrote that the National Park Service had tested the soil before the White House garden was planted and found lead levels of 93 parts per million and called the levels toxic.
A Web site called Sludge Watch contacted me to report that the lead levels were the result of sludge dumped on the White House lawn by the Clintons to improve grass growth.
Almost immediately, Obama Foodorama, a well-crafted and thoroughly reported blog about everything "food" in this White House, from presidential birthday cakes to the first lady's campaign for healthy eating and cooking, debunked the story.
Blogger Eddie Gehman Kohan contacted three soil scientists, all of whom dismissed 93 ppm as "ridiculously low" for an urban garden and said no harm could come from humans eating from that garden, even if they consumed handfuls of the dirt itself.
If indeed sludge had been used to fertilize the lawn — a practice used in the 1980s — any harm would have dissipated in the decades since, the scientists said.
But speaking of fertile soil, the Internet is a place where misinformation lives forever, and the story of "Michelle's Toxic Veggie Garden," will not die.
Every day since the Mother Jones story in June, another blog, Web site, newsletter or crackpot — even legitimate publications here and abroad — regurgitates the toxic-garden story and adds to it, so that now we read that Michelle Obama will not allow her family to eat from the garden, and, since the produce is being sent to Miriam's Kitchen in Washington to feed the poor, innocent children will have their brain development and their futures stunted by the lead levels in that food.
One such story received a comment from a reader that seemed to pull all the Obama conspiracy theories together: Michelle Obama would have known better than to plant vegetables in such a space if her "old man" hadn't been born in Kenya.
I don't know about you, but all these conspiracy theories are starting to make me feel paranoid. Not because I believe Dick Cheney directed Israel's Mossad to bring down the World Trade Center but because there are lunatics out there passing themselves off as journalists, and that is making the rest of us look really bad.
David Aaronovitch, columnist for The Times of London, calls such nonsense "voodoo histories," and he debunks a number of them in his new and highly entertaining book by the same name.
He writes that we are going through a period of "fashionable conspiracism."
When we try to make sense of the world, we can't bring ourselves to believe that things happen because of bad luck or the work of a few malevolent individuals. So we construct a world in which events are manipulated by secret hands. We don't want to believe our government is run by incompetents, so we spin up the notion that is run by an all-knowing, secret society.
But the problem with conspiracy theories, Aaronovitch argues, is that they always libel a group or an individual, with sometimes horrific consequences. "The Protocols of the Elders of Zion," a work of fiction that outlined a supposed Jewish plan to take over the world, was used by the Russians before World War I to inspire the pogroms, by Hitler to inspire the Holocaust and by Islamic extremists today.
Michelle Obama did not "fake" the White House kitchen garden with mature plants to fool the public (another conspiracy theory), and it does not contain deadly levels of lead. (Her press office continues to patiently issue this assurance.)
Michelle Obama always wanted to have a garden. She planted one at her new home. She is using it to promote healthy eating because unhealthy eating is at the root of so much suffering among city dwellers and the poor. Her family often has its produce for dinner.
This is Occam's razor, the principle Aaronovitch uses to dismantle history's favorite conspiracy theories: The simplest explanation is usually the right explanation.
E-mail Reimer at email@example.com