In 2016, I suffered a serious ski injury. It occurred on an easy run and I don’t even know what happened. One moment I was skiing along and then next I was missing a ski and crashing. Not knowing what caused the crash is unsettling — if I knew what had caused the fall I’d avoid it in the future — wherea the lack of apparent cause highlights the lack of control I have over my life. Once, when I expressed this sentiment to a friend, he said, “I guess it was just bad luck.” True.

Sometimes our actions are the direct cause of events while other times incidents that affect us have random external causes. Here’s an example: about 10 years ago I rear-ended another car because I looked down to fiddle with the radio. This accident directly occurred because of something that I did. While I was upset with myself for my poor driving it did not create an existential crisis for me as my ski accident did. In contrast, the driver of the car I hit experienced bad luck — she was just driving along and minding her own business, and then “wham” I hit her. She experienced bad luck while my part of the accident was just bad driving.

Another way to think about luck is that “shit happens.” An adolescent at the time, I remember with glee when this phrase entered the vernacular in the early 1980s.* Like the related pithy 1980s phrases “life’s a bitch, and then you die” and “where’s the beef?”, “shit happens” is quite philosophical. It suggests that we are bobbing along on a sea of randomness and events over which we have no control and often occur without warning can have big life impacts. Digging a bit deeper, “shit happens” links the concepts of luck and randomness.

Randomness refers to things that transpire by chance at the system level. For example, the pattern of coin flips or numbers drawn in the lottery are random. But randomness can also occur due to the complex interaction of intelligent actors. For example, every day there are thousands of car crashes (about 16,000) as the result of millions of drivers interacting on our roadways. We can’t predict any single accident but we know that crashes will occur and about how many within a range. As such, even though car crashes are usually caused by human action, they are randomly distributed and each trip in a car involves the possibility you’ll be in a wreck.

Luck is the application of randomness to individuals. For example, the lottery is random but if you happen to have the winning numbers you are lucky. If someone makes an improper left turn in front of you just as you are driving through an intersection and you hit them you are unlucky. And sometimes ski binding just pops loose without warning, and when it happens to you it is bad luck.

Thus randomness and luck are the flip sides of the same coin. I’ve found that it’s useful to think about randomness and luck differently. Accepting that the world is rife with randomness and that existing means there is a level of irreducible uncertainty is uncomfortable because the resolution of uncertainty is a primary human motive. But adopting a worldview that shit happens (both good and bad) can provide a sense of equanimity. Knowing that we aren’t totally in control, just riding the waves of randomness inherent in life, and taking good and bad luck as it comes can provide a sense of peace.

*The etymology of the phrase “shit happens” traces to a 1983 book cataloging slang used at the University of North Carolina at Chapel Hill published by UNC professor Connie Eble.