How I was able to control the weather

Alternative title: how I learned that correlation ≠ causation

It was quite odd, really. As a kid, I could control the weather. I was, after all, the main character of this world. Cogito ergo sum; I can only be certain of the self, and therefore it makes perfect sense that I am at the centre of the universe. … alright, I’ll put a brake on the sarcasm for now. But, you see, I really felt like I could control the weather, and I had no better explanation for it.

Somehow, when I was feeling down, the weather would be dreary. Middle grey skies. No glimpse of the sun to be seen. Not a single distinguishable cloud to be spotted. Yet, on a completely different day, when I noticed I was feeling particularly joyful, the sun would be shining brightly with clear blue skies as far as the eye could see. I had only one explanation for this. And so I told all of my friends about my superpower: I could control the weather with my mood! And they believed me, of course. They noticed that I was happy on sunny days, and less so in the rain. My explanation made perfect sense to my peers.

It wasn’t until many years later that I had my epiphany. I wasn’t controlling the weather with my mood (surprise). I just couldn’t think outside my box of limited life experiences. I never questioned whether the causation between my mood and the weather could be the other way around. Maybe, perchance, the weather affected my mood, instead.

There are surely some lessons to be learnt here:

1. Correlation does not equal causation. Of course, just because of the happenstance that two things tend to occur at the same time, doesn’t mean that one of these is the cause of the other. In fact, there’s a beautiful website by Tyler Vigen that shows spurious correlations in seemingly unrelated datasets. My favourite one is where the cheese consumption per capita correlates with the number of people who died being tangled in their bedsheets. Obviously, eating cheese makes you more tangleable in bed.
   
2. Take confirmation bias seriously. It happens quite often to the best of us. It’s how our brains are wired for efficiency. As a kid, whenever I noticed that being happy correlated with the sun shining, it reinforced my notion of being able to control the weather. Similarly, as an adult, we might find that news about violence reinforces the idea that our neighbourhood is unsafe. But we need to stay reasonable and look at empirical evidence to determine whether our neighbourhood is actually any less safe than before. As a human, you and I both more easily remember things that we want to hear. Let’s keep this bias into consideration when making big decisions.
   
3. Don’t put blind trust in a kid, especially when they tell you something that goes against scientific reason. Actually, you might want to pretend to be amazed to avoid shattering their hopes and dreams again, but don’t put your kid in your backyard, burn their plushies and expect their current bad mood to bring forth a rain dance that will save your three already withering tomato plants from imminent global warming.