This post is full of holes and simplistic reasoning; I'll just pick one instance: Logging is a side effect Right -- inside of a pure function, logging is prob

This post is full of holes and simplistic reasoning; I'll just pick one instance: Logging is a side effect Right -- inside of a pure function, logging is probably not a great idea. But in other parts of your code (that are already generating "side effects" -- because you know, that's what software does) -- it can be not such a bad idea.