I mentioned in my last post that the The Art of War, Hagakure, Book of Five Rings or Tao Te Ching, are instructive for the modern manager.
These books are, in part, about the formation of priciples. The rules we apply to the living of our lives.
If you're looking for a modern guide to this, I recommend Ray Dalio’s Principles. At it's core he suggests you, "think for yourself—to decide 1) what you want, 2) what is true and 3) what to do about it."
Principles are concepts that can be applied over and over again in similar circumstances as distinct from narrow answers to specific questions. Every game has principles that successful players master to achieve winning results. So does life.
Principles are ways of successfully dealing with the laws of nature or the laws of life. Those who understand more of them and understand them well know how to interact with the world more effectively than those who know fewer of them or know them less well.
Different principles apply to different aspects of life—e.g., there are “skiing principles” for skiing, “parenting principles” for parenting, “management principles” for managing, “investment principles” for investing, etc—and there are over-arching “life principles” that influence our approaches to all things.
And, of course, different people subscribe to different principles that they believe work best.
— Ray Dalio, Principles