> As the joke goes, there are two hard problems in computer science: cache invalidation and naming things. But I’d suggest there’s a much harder problem, namely, =. Did you miss it? The equals sign, =, is small, but I’m going to argue that the use and misuse of equals is at the root of a large number of problems in software engineering.

Equality Is Hard — Craig Stuntz
https://www.craigstuntz.com/posts/2020-03-09-equality-is-hard.html