November 2024. Part of “Letters from the Lab”, a series of informal essays on my research written for patrons. You can also listen to this essay (14 minutes).I want to create a new kind of spaced repetition system—a new kind of enabling environment—with a different central primitive.The need for a new central primitiveThe central primitive of existing spaced repetition systems is the flashcard. If you want to remember some fact, you transform it into flashcard form and add it to your system. The...