Writing has been historically used as a means of understanding the world around us, and there is extensive research supporting the benefits of writing as a tool for thinking. Meanwhile, with the advent of the internet, all human knowledge has become universally accessible. Physics equations, nutrition facts, programming idioms, disease symptoms, can all be found in seconds. What is worth keeping note of then?
Many ideas are obvious, and make intuitive sense, while some are surprising. Initially they don’t make sense at all, until a euphoric moment of clarity where everything ties together. Other ideas make so much immediate, intuitive sense that they are equally surprising.
Claude Shannon, a pioneer in information theory, measured the amount of information contained in a message by how surprising it is. I try to take note of things that surprise me. This seems to be a reliable heuristic for what’s worth keeping note of.
What was I surprised by, why, and how I ultimately came to understand the concept. Apart from helping me understand the concept better, writing allows me to track how my understanding evolves over time. When I revisit my notes, I can compare my initial reaction to an idea to my brain’s current interpretation.