Zettelkasten, a method for note-taking

Having a repository for the things you learn is more relevant than ever. Facts can be easily checked using the internet. However, the process of connecting ideas, and formulating relevant questions, comes from deep reading and reflection.

Last weekend I discovered a method for note-taking called Zettelkasten. This method was devised by German sociologist Niklas Luhmann, who used it as an aid in his research throughout his life1. For context, during his life Luhmann published more than 70 books and 400 scholarly articles on various subjects. Luhmann referred to his Zettelkästen as his zweites Gehirn, his second brain2.

Most of the things I’ve learned about Zettelkästen comes from the excellent zettelkasten.de website by Christian Tietze and Sascha Fast. At first, I thought about buying Sascha Fast’s book Die Zettelkasgtenmethode to learn the method. But alas, there’s no ebook version available. Having it shipped to Peru, aside of time issues, almost doubles the price of the book. So I resorted to reading enough of the articles on the website to gain a working knowledge of Zettelkasten.

A Repository for Knowledge

The basic idea behind Zettelkasten is to build a repository of the knowledge you gain through the years. The idea is similar to what Paul Jun, of Creative Mastery, writes about keeping a Commonplace Book, or Ryan Holiday’s notecard system. Zettelkasten adds the powerful idea of linking notes to create a web of interlinked knowledge.

I’ve been taking notes of what I read for years, first on index cards, then Filemaker, then Evernote and, more recently, using Bear. After a couple of days of appying some of the concepts of Zettelkasten, I’m really impressed in how my understanding of what I read has improved, and more important, the consistency of the system.

Instead of explaining the technique by itself, I’ll describe how I’ve incorporated it into my reading workflow.

I read most of my books on the Kindle, either using the physical device or the MacOs app on my laptop. While reading, I highlight paragraphs as I see fit, and add notes using the corresponding feature on the Kindle.

Later, on the Kindle app on my laptop, I process the highlighted paragraphs and notes. I copy each highlighted paragraph to Bear, using a separate note for each concept. (Zettelkasten refers to this as atomicity.) Each note is given a unique identifier and an appropriate title3.

Each note is also given tags for classification. Good tagging helps with accuracy when searching. The method’s recommendation is to use tags for objects, and not for subjects4. In the same note, I write down the ideas I had in mind when highlighting the paragraph, or any connection that comes to mind during this process.

Context notes are used as a map to a series of notes. A context note that outlines a more complex concept or broader subject, using links to other notes in the process. For example, while I’m reading a book, I build an outline of the things I find relevant, based on my highlights and notes of the book. Each of the outline’s items links to a separate note explaining the idea in more detail, and usually contains the highlighted text of the book.

While this process takes more time, it helps with understanding what you read at a different level, and making connection with other concepts and ideas. I’m interested in reading more books, but not if it goes against comprehension.

Update 2020-11-08: If you want a more systematic approach to Zettelkasten, check this excellent introduction by Sacha Fast.


  1. I’m not writing to endorse Luhman’s sociology theories, because I don’t know anything about them. This article is about his note-taking method. 

  2. cfr Ein Zettelkasten war Lumens zweites Gehirn

  3. I’m using the recommended format in the Zettelkasten.de site of date-time to create a unique identifier. For example, 20181113131025 for a note created on 2018-11-13 at 13:10:25. (I actually use TextExpander to create the ID automatically.) The note title becomes then “20181113131025 Cultural assimilation in empires” instead of “Cultural assimilation in empires”. This ensures that each note is uniquely identified. 

  4. Check this article by Sacha Tietze for some insights on how to use tags effectively: The Difference Between Good Tags and Bad Tags


Featured image photo by Aaron Burden on Unsplash.

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