Here's what I know for sure

There are three depths of knowing.

  1. Hearsay: You’ve heard of the president. You’ve heard of Mt. Everest.
  2. Introduction: You’ve been introduced to the President. You’ve visited Mt. Everest.
  3. Intimately: You’re a good friend of the President. You’ve climbed Mt. Everest.

Understanding comes when you wrestle with these questions:

  1. What is the most sure thing to you? 
  2. What would be the most impossible thing to doubt?

Stephen Goforth