Spaced repetition is a scientifically proven method of memorizing information and retaining knowledge. Its true value lies in being able to recall things in different contexts. The goal of mastery is being able to remember relevant information at the right time.^[Readwise Blog. “Using Spaced Repetition and Active Recall with Books to Hack Your Brain,” September 15, 2019. https://blog.readwise.io/hack-your-brain-with-spaced-repetition-and-active-recall/.]