Since the rapture was such a popular topic over the weekend, an obvious came that came up quite a bit was, “what will these people believe when May 21 comes and goes raptureless?” My answer to this–and many other people’s answer–was that it will somehow be rationalized with my personal favourite rationalization being of the “we didn’t believe in it hard enough” variety. I was wrong. Not about the rationalization but about which rationalization. From the New York Times referring to Harold Camping, the guy who came up with the whole May 21 rapture business:

What he decided, apparently, was that May 21 had been “an invisible judgment day,” of the spiritual variety, rather than his original vision of earthquakes and other disasters leading to five months of hell on earth, culminating in a spectacular doomsday on Oct. 21 — something he had repeatedly guaranteed. On Monday, however, Mr. Camping seemed satisfied with his new interpretation, which apparently spared humankind its months of torture for a single day of destruction.

Camping may not know it, but he was eloquently abiding by an important rule of statistics:

I know, I know, it means nothing to you. This equation is the basis of an entire philosophy of statistics but, without getting into it, somewhere in there it says that if you believe something with 100% confidence, nothing will change your mind. If you’re absolutely sure about something, there should be nothing I can say or show you, no experiment I can do, no time machine I can build, that can change your mind. And, in case you didn’t notice, that’s a problem. It’s also creates a weird world where I can’t even say with 100% certainty that I had corn squares cereal for breakfast this morning. From Julia Galef’s post on Measure of Doubt:

Belief isn’t binary. Or at least, it shouldn’t be. In reality, while we can be more confident in the truth of some claims than others, we can’t be absolutely certain of anything. So it’s more accurate to talk about how much we believe a claim, rather than whether or not we believe it. For example, I’m at least 99% sure that the moon landing was real. My confidence that mice have the capacity to suffer is high, but not quite as high. Maybe 85%. Ask me about a less-developed animal, like a shrimp, and my confidence would fall to near-uncertainty, around 60%.

Wait a second, I guess this means that I have to say that I believe it’s more likely to be true that I ate corn squares cereal this morning than the moon landing was real. Weird. Anyway, all this talk about belief–this was supposed to be a post about the rapture–reminds me that Robin Hanson of Overcoming Bias tells us that we shouldn’t believe in the first place:

In my experience “I believe X” suggests that the speaker has chosen to affiliate with X, feeling loyal to it and making it part of his or her identity. The speaker is unlikely to offer much evidence for X, or to respond to criticism of X, and such criticism will likely be seen as a personal attack.

Feel the warm comfort inside you when you say “I believe” – recognize it and be ready to identify it in the future, even without those words. And then – flag that feeling as a dangerous bias. The “I believe” state of mind is quite far from being neutrally ready to adjust its opinions in the light of further evidence. Far better to instead say “I feel,” which directly warns listeners of the speaker’s attachment to an opinion.

Can I still say, “I believe the Canadiens will win the Stanley Cup next year,” and get that warm feeling? I guess so as long as I don’t bet my life savings on it.

I suppose this is another reason it was hard for Harold “Invisible Rapture” Camping to admit he might have been wrong about the whole thing. He has a lot invested personally and possibly even financially although it’s hard to think how you could benefit financially from the rapture. It’s still hard to keep a straight face, though, when Camping says about May 21, “The world has been warned.” A beautiful day, reading in the sun–best warning ever.