Marco Betschart


A method to organize knowledge in the way we think: as an entangled web of information.
The "Zettelkasten" is a note-taking system invented by Niklas Luhmann, a German researcher who is considered one of the most important social theorists of the 20th century.
"Zettelkasten" is German for "slip box" or "card index".
A Zettelkasten enables you to to organize your notes into an entangled web of information. This in turn allows you to discover new ideas and connections between your notes which otherwise would have been kept hidden.
The bigger your Zettelkasten grows, the valuable it gets: Imagine a Zettelkasten which contains thousands and thousands of ideas. If you now have a specific question and start to explore this Zettelkasten it will provide ideas which you've already forgotten a long time ago - thus it will probably answer your question in surprising ways.

The 12 Principles of a Zettelkasten

To make the most of a Zettelkasten, you should follow these 12 principles:

1. Atomicity

Each note should contain one idea and one idea only.
This is key to link ideas.

2. Autonomy

Each note should be self-contained and comprehensible on its own.
This ensures notes
  • can be moved, processed, separated, and concatenated independently of its neighbors
  • remain useful even if the original source of information disappears
Whenever you add a note, make sure to link it to already existing notes.
"A note that is not connected to the network will be lost, will be forgotten by the Zettelkasten" - Niklas Luhmann
Whenever you are connecting two notes, make sure to briefly explain why you are linking them.
This is key to ensure you know why you connected the notes in the first place - even it is years down the road.

5. Use your own words

Use your own words to express an idea, so your future me is able to understand it - even years later.
Don't copy & paste!

6. Keep references

Add the reference to the original source to your note.
This makes it easy for you to revisit the original source later on.

7. Add your own thoughts

If you have thoughts of your own, add them as notes.
Make sure you adhere to the principles of atomicity, autonomy, and linking.

8. Don't worry about structure

Don't waste time thinking about a neat folder structure or preconceived categories.
The Zettelkastens organization develops organically.

9. Add connection notes

When you start seeing connections among notes, create "connection notes". Their purpose is to link together other notes and explain their relationship.

10. Add outline notes

An outline note is a note that simply contains a sequence of links to other notes, putting those other notes into a particular order to create a story, narrative, or argument.

11. Never Delete

Instead, link to new notes that explain what’s wrong with the old ones.
This way, your Zettelkasten will reflect your thinking over time.

12. Add notes without fear

You can never have too much information in your Zettelkasten.
The bigger your Zettelkasten grows, the valuable it gets.

Further Reading