> Writing is not what follows research, learning or studying, it is the *medium* of all this work. > > — Sönke Ahrens, *How to Take Smart Notes* (2022: 2) A *Zettelkasten* (German for “slip box”) is a collection of notes that grows into a network of ideas. Its best-known user, the German sociologist Niklas Luhmann, published 58 books and hundreds of articles, and credited his slip box for it (Ahrens 2022: 13). He wrote each idea on its own index card, gave it a number, and filed it behind a related card, with references to others. Sönke Ahrens’s *How to Take Smart Notes* made the method widely known again. His argument is that note-taking is the most neglected part of writing, because we do it every day and “we don’t experience any immediate negative feedback if we do it badly” (Ahrens 2022: 2). A Zettelkasten supplies the missing feedback: every time you return to your notes, you see what you understood and what you didn’t (Ahrens 2022: 51). My own interest in note-taking began when I was looking for a better note-taking app and came across Obsidian. I had no idea how to use it, so I started watching tutorials, and one of them recommended *How to Take Smart Notes*. The book completely changed my approach to note-taking and learning in general. ## Three kinds of notes Ahrens distinguishes three kinds of notes, each kept in its own place (Ahrens 2022: 39–40): - **Fleeting notes**: quick reminders of an idea, thrown away once they’ve been dealt with. - **Permanent notes**: notes on what you read, kept with your sources, and notes with your own ideas, kept in the slip box itself. - **Project notes**: notes for one piece of writing, kept with that project. Highlighting and margin comments are fleeting notes too. As Ahrens puts it, they “do nothing to elaborate on a text” (Ahrens 2022: 41). Understanding begins when you put what you read into your own words. ## What makes a good note Whatever its medium, a note in a Zettelkasten should be (Anderson 2023): - **Atomic**: one idea per note, so it can be linked and reused on its own. - **Connected**: linked to the notes it relates to, so ideas meet each other. - **Yours**: written in your own words, not copied. Luhmann used paper. Today most people keep a Zettelkasten in a note-taking app such as [[Obsidian|Obsidian]], where links between notes take a keystroke. The principles are the same. ## Why it works The slip box isn’t just storage. In Ahrens’s words, “we need a reliable and simple external structure to think in that compensates for the limitations of our brains” (Ahrens 2022: 20). That is Clear’s point about systems, applied to thinking: the structure does what memory and willpower can’t. ## A caveat Reviewing the first edition, Melanie Schiller praised the book as readable and as an argument for the humanities, but noted that it never asks whether a method for producing more writing feeds the pressure on academics to produce more (Schiller 2017). The method serves thinking best when it isn’t treated as a machine for output. ## Where to start Rather than getting hung up on note types and organization, my advice is to just start somewhere with Ahrens’s overarching principle in mind: “Writing is the only thing that matters” (the title of his fifth chapter; Ahrens 2022: 33). The next time you read, just take notes as you go. As soon as you’ve finished reading a section or passage, try to summarize *in your own words* the author’s main points. Don’t get hung up on perfection. The more you practice summarizing and paraphrasing, the better you get at it. ## References Ahrens, Sönke. 2022. *How to Take Smart Notes: One Simple Technique to Boost Writing, Learning and Thinking*. 2nd ed. Hamburg: Sönke Ahrens. Anderson, Morgan, dir. 2023. “How to Take Notes That ACTUALLY Help You Think and Write.” YouTube video, November 10, 2023. <https://www.youtube.com/watch?v=JYHcU4ZkCQo>. Schiller, Melanie. 2017. Review of *How to Take Smart Notes: One Simple Technique to Boost Writing, Learning and Thinking for Students, Academics and Nonfiction Book Writers*, by Sönke Ahrens. *Journal of Writing Research* 9 (2): 227–31. <https://doi.org/10.17239/jowr-2017.09.02.05>.