I learned capacity for self-reflection very early, finding it through interior monologues that books are so good at and that visual media is so bad at because it's so boring - nothing's happening. In a book, you can be inside the narrator's head for 50 pages, and nothing needs to happen. Then you learn to be inside your own head without something needing to happen. It's a very good antidote to a crazy, restless, "what's next?" culture - that you can just be in your own head and nothing is happening except that this is a rich place. I love that.