I’ve learned a couple tricks to these essays. One is that I can always make them longer, and do. I’m trying not to. Another is in how to pick fruitful subjects. There’s always some chance to this and I’m still being surprised. But if I’ve found anything to be a sure bet, it’s picking the candidate topic that seems to be about the most obvious property. For example, everyone interested in mathematics knows about commutative things. But these are great because they make me focus on some “obvious” bit of mathematics lore. The “commutative” essay, in 2018, was an example of this. I didn’t achieve an insight to match that of “asymptote”, in which I finally understood a thing I had known for decades. But I improved my understanding at least.