Searching for live principles

I saw this discussion on HackerNews " What mental models do you use everyday?" and reading it my first thought was "wow these are some great summaries of maybe some life principles".

As I thought more about it, I realizes that for almost every principle/mental model shared there, there are some important edge cases. I think then that it is required not only to know the mental model and when to apply it but also to know when to not apply it.

I also feel that some of them are too general to be useful and most of them are close to life principles or maybe some kind of philosophy about how to live our lives.

I then started thinking about what or how would a good life principle sound like?

Here is my thesis on this:

A good life principle is one that requires very few axioms to make it true or fit for any person.