The Zettelkasten - How to Take Smart Notes

The Zettelkasten is a system for taking notes and knowledge management made famous by prolific German sociologist Niklas Luhman and summarised to a modern audience by Sonke Ahrens in his book “How to Take Smart Notes” [1]. The underlining principle of the system is to act as a second brain, facilitating connections and discovery of insights. The method can be summarised in the following steps:

  1. Whenever you think of something, a fleeting thought, write it down in a collection of notes known as your fleeting notes.
  2. Whenever you read/watch/listen for knowledge, ensure you are doing so with a pen in hand so that you can actively take notes on it using your own words. Keep this collection of notes closely linked to a reference system, forming together your literature notes (how do I read scientific literature?).
  3. Make permanent notes ( zettels ), as soon as possible. Ensure that
    • you ask yourself how these new ideas relate to your existing notes.
    • you have only one idea per note.
    • the notes are atomic: they can be read independently of other notes
    • the notes are resilient: they are written well enough to still be understood far in the future.
  4. “Position” the new zettels within your notes, the slip-box, the Zettelkasten:


[1] Ahrens, S. (2017). How to Take Smart Notes: One Simple Technique to Boost Writing, Learning and Thinking for Students, Academics and Nonfiction Book Writers. Sönke Ahrens.

Notes mentioning this note

Here are all the zettels in this zettelkasten, along with their links, visualized as a graph. You may need to zoom and pan around to see something.