As I mentioned in a previous post (“Courage”), I lost contact with my favorite (best) teacher in high school – until “remarkably” I bumped into him several years later when we both had made Aliyah and landed at the same Israeli institution: Bar-Ilan University. What an amazing coincidence! Well, coincidence, yes; amazing, not really.
Everyone has had at least one remarkable coincidence happen to them in life, probably several that left us flabbergasted. We find it so incredible that we usually can’t stop thinking about it or relating it to others. Well, I’m sorry to be a party-pooper, but coincidences are really no big deal.
Let’s take my own example from above. There are two ways of looking at this:
1) What are the chances that I would bump into a person I know well – both of us thousands of miles away from where we had our relationship? Put this way, the chances are very low.
2) How many times did I walk around Israel and not bump into someone that I knew from back then? The answer: several hundred times a day.
Now multiply #2 by all the days in the year, and we have thousands of non-coincidences! But we don’t think about these because they didn’t happen. A person would have to be completely crazy to go about life thinking every second about what did not occur at that moment – and if s/he did try to do that, s/he would very soon become crazy!
Coincidences, then, are simple statistical anomalies – what are called outliers. In any situation, there are the “normal” things that happen (and the vast majority of things that do not happen), and then there are the rare things that happen (or don’t occur e.g., a baby climbing and falling out the fourth floor window and not breaking a bone because the mattress delivery men just happened to be bringing one at the entrance to the building). Human psychology, of course, picks up on (and remembers) the “abnormal” event precisely because it is not normal.
In reality, we see this phenomenon everywhere in our life, not only regarding “coincidences”. We walk down the block and pass hundreds of people – but the one that sticks in our mind is the 6’10” (2.10 meters) guy built like a tank. Do you recall any of your losing poker table hands, or the one where you bluffed your way to a huge jackpot?
From this perspective, “amazing” coincidences are, paradoxically, proof of how routine our lives really are. When we are part of a coincidence, it makes us stop and shake our heads in wonderment. But that’s really the time to consider how infrequently a coincidence actually occurs – and why.
Finally, there is another type of “coincidence” – the statistically spurious one. Here’s a classic example: if you went to a party, what number of people at the party would have to be present for there to be a 50-50 chance of two attendees having the same birthdate? (Don’t peek below; first make an educated guess.)
Some people will say: 182 (half of 364); others will understand that there are “permutations” here and lower the number to around 100. Here’s the statistically correct number: twenty-three!! Now imagine being at a party of 30 people (not having read this mini-essay of mine) – and in the course of the party chatter you hear two people laughing out loud: “Wow! Amazing that we have the same birthdate!! What are the chances of that?!?” It becomes the dominant conversation of the party, and you wonder at the coincidence. But now you know that with thirty people in the room the chances were far better than “even” that two partygoers would have been born on the same day/month on the calendar.
Such statistical “anomalies” can be found everywhere in life. As most of us are not particularly mathematically literate, we see “coincidences” everywhere. So calm down: it’s just normal mathematics at work – plus a healthy dollop of human psychology not working so well.
P.S. None of this is to say that an “amazing coincidence” can’t occur. My all-time favorite: the second and third U.S. presidents – John Adams and Thomas Jefferson – both died on the exact same day pretty amazing, right?): July 4, 1826, exactly 50 years to the day from the signing of the Declaration of Independence, of which both men were signees! Now that’s worth shaking your head over…