Eventually in my moving on, I got to Facebook, where I discovered that two celebrity deaths is not enough. One friend was “weirded out by the three celebrity icons that have passed away recently… Ed McMahon, Farrah Fawcett, and Michael Jackson.” Then there was ” Wow….I know these things seem to happen in threes, but wow.” and “Hopefully Ed McMahon was recent enough to fulfill the law of threes…” and “It happens in threes. It happens in threes.”

The idea even made the news.

Apparently, not everyone was in agreement that Ed McMahon was sufficient to round out this menage, however. A quick look at Twitter found Jeff Goldblum in the trending topics. Searching turned up a combination of Tweeters debunking and passing on the rumor that Goldblum had died…and plenty of references to the idea that these things happen in threes, an idea that may have contributed to the acceptance of the hoax. (A smaller stream of rumor followed a similar hoax regarding Harrison Ford.)

Let me just say this straight out. These things do not happen in threes, and it takes some weird ways of looking at the world to suggest that they do. Now, we’re wired to look at the world in some pretty weird ways, I admit, but we don’t have to stop there.

A quick current look at Wikipedia’s list of celebrity deaths for yesterday lists a dozen people. Admittedly, many of these celebrities are not anyone my circle of friends would have heard of, as they don’t follow Indian politics or Belgian pop music, but does that mean these people don’t count? How about the other three Americans on the list, two writers and a rock singer. Do they count?

Suppose we decide this “law” only applies somehow to people we’ve heard of (and no, I’m not going to try to figure out how this law knows to restrict itself to action within certain social groups). That favors a menage that includes McMahon. However, Wikipedia tells us that on the day McMahon died, Jerri Nielsen also died, making four instead of three.

But you’ve never heard of Jerri Nielsen, you say? Oh, yes, you have. She’s the doctor who treated herself for breast cancer while trapped at the South Pole over the winter. Her book was a bestseller, and her story inspired both a movie and an episode of House. In the last 10 years, she’s been much bigger news than McMahon and his sweepstakes promotions, even if her death got less attention. Still, we have to set her aside to have our threes.

It should be becoming obvious by now that the rule of threes is a tidy example of confirmation bias, or the fact that our brains are better at arranging, attending to and storing information that supports what we already think than data that contradicts our beliefs. I’m not talking about some form of intellectual dishonesty, but simply the fact that it takes us much less work to recognize something than it does to discover something new and figure out how it fits into the world.

It was, in fact, fascinating to watch how confirmation bias played out in the case of the Facebook friend who was weirded out. Someone suggested to her that David Carradine and Bea Arthur had also died recently. She responded by saying they were both part of the previous three. So I decided to see whether I could figure out who the third person was.

Looking at celebrities who died between Arthur and Carradine, I quickly came upon fantasy author David Eddings, whose death definitely made an impression on her. Aha! I had our three.

Then I found Dom DeLuise, who would have been as much a part of her childhood as he was of mine. DeLuise was Hollywood, so she probably meant him. But counting DeLuise because he was Hollywood means we really shouldn’t overlook Carole Cole, who also died between Arthur and Carradine.

Still, not being able to come up with an obvious three wasn’t the most fun part of my exercise. That was discovering that the two people she’d grouped in the “previous three” had died more than a month apart. Bea Arthur died April 25. David Carradine died June 3. That just wasn’t how she remembered it.

This doesn’t just happen to true believers, either. Even people who were arguing against the idea that things come in threes were compressing time once people had made associations between events. Two people thought McMahon died on Wednesday instead of Tuesday. Time compression in memory happens even among skeptics, which tells us how much work it is to fight confirmation bias.

Bad news happens in threes because we ignore the rest of the bad news. Bad news happens in threes because our memories elide the time in between us hearing about the deaths that shock us. Bad news happens in threes because we pay attention to the times when three things happen instead of two or four or eleven. But bad news doesn’t come in threes because these things always happen in close groups of exactly three like events, even when someone tells you they do.

So the next time you’re feeling weirded out because two bad things have already happened, deal with those instead of worrying about what’s coming next. Something will come, but it will come on its own schedule and may well be good rather than bad. No laws. No rules. Just life.