I spent the last month revisiting my notes from 200-some books. As I moved through topics spanning health, entrepreneurship, philosophy, learning, and everything else I’ve been interested in, I couldn’t help noticing some trends, some categories of thought the books could be organized into. When I started reading more energetically, I focused on practical, how-to style self-improvement books. The Power of Habit. I Will Teach You To Be Rich. The $100 Startup. Popular books that promised to teach me a “hack.” Eventually, I grew bored of books that could be condensed to a blog post and pursued higher level books. Peak. Seeking Wisdom. The Monk and the Riddle. Books that provided a broader understanding, a richer context for their ideas.