It's one thing to believe, in a sort of vague and nonspecific way, that the world will end one day. It's another thing to believe that it's going to happen on Saturday, May 21, 2011, which is what Harold Camping, a dogged and committed Christian broadcaster from Oakland, California, believes with all of his might.
It's a complicated maths problem, of course, to crunch the numbers and come up with a date certain for the End Times, but Mr Camping has done just that. Even more, he's convinced untold listeners of his Family Radio stations - found on short wave, internet, satellite and everything else - that Saturday, May 21 is Judgement Day.
Hundreds have taken to the highways and back roads of America to spread their message of doom and redemption. Travelling across the continent in ragtag convoys of RVs and old busses, they've got barely a week left to evangelise the population into renewed faith, atonement for sin and general preparation for the fiery end of the world. On the one hand, it's a tough sell. On the other, it's a lot easier, probably, when you're working with a firm deadline.
But it would have to be organised for a Saturday, wouldn't it? Saturday is a universal day off. It would make marketing it a lot easier if Mr Camping could crunch the numbers one more time and come up with an apocalypse that coincides with the start of the week, don't you think? I don't know about you, but there have been many weekday mornings when I've prayed for the end of the world. Saturdays, not so much. On Saturdays, I like to go to the beach.
Look, a lot of us have something we're afraid of, something huge and apocalyptic and on the way. If you live in California, it's "The Big One", the 11.3 earthquake. For science fiction fans, it could be some giant asteroid crashing into the earth.
Survivalists and people like that - you know the type: prepared for the apocalypse with a hideout in the desert and stockpiles of canned tuna and chlorine tablets and crossbows - don't even bother to predict the actual specifics of the civilisation-ending calamity they're preparing for. They just call it "The Event" with alarming vagueness.
The followers of Mr Camping don't bother with the aftermath of their version of The Event. In their view, the deserving will be spirited up to Heaven, and the undeserving will suffer the fires and volcanoes and earthquakes of the end of the earth. It'll be like the movie 2012, I guess, but with no one left to root for. All the good guys, apparently, will already be in a better place.
Again, it's easy to make fun of the Christian Doomsday Caravaners. Maybe they're paranoid and unhinged. But when you think of all of the terrible, destructive things that can happen - and do happen - anywhere in the world, what, exactly, is paranoid? Who, exactly, is unhinged?
A confession: I get an e-mail, twice-daily, from the International Society of Infectious Diseases. It's called the ProMED e-mail, and it lists in excruciating detail the various infectious diseases that have been reported that day, worldwide - all of them, human, plant and livestock.
Why did I sign up for this? Beats me. But I think it's because I travel a lot, and one of the things I've noticed is how close we are, all of us - despite living in nice neighbourhoods in nice places - to a lot of scarier, dirtier places.
By "close" I mean this: a guy from a remote village in China or Africa or wherever has a strange infectious disease - maybe he got it from livestock; maybe he got it from a weird insect; maybe he just got it - and he gets on a train or a bus or a plane. Before you know it, New York, Los Angeles, Dubai and Frankfurt are all Petri dishes of some odd, unexplainable and probably disgusting disease.
Mr Camping comes up with the end of the world next Saturday. I get an e-mail from a global NGO and I scan it for the first sign of an odd disease somewhere I've never been to, somewhere I'll never go. But we're both looking for the same thing. We're both looking for a little advance notice, a little "heads up" that the end of the world is nigh.
Mr Camping and his followers are going to use that extra time - which they pinpoint at about seven more days - to save some other souls, which actually shows them to be awfully good-hearted folks. Personally, when I get a ProMED e-mail that seems to spell The Event, I'll head for the hills and wait it out.
As you've no doubt realised, the end of the world isn't going to bring out the best in me. But be honest now: will it bring out the best in you?
Rob Long is a writer and producer in Hollywood