A zettelkasten is a method of personal knowledge management inspired by the sociologist Niklas Luhmann. These notes explain what the system is, what it is for and how its notes are sorted. Its purpose is to generate ideas from linked notes, and surprise is the mechanism that produces them. The book-level argument and the writing process are covered in Ahrens on the slip box, which these notes point to where the ground overlaps.
1Luhmann's zettelkasten
Zettelkästen is the German word for "slip box". Whenever Luhmann read something, he recorded the bibliographic information on the source and some brief descriptive notes about the content on either side of a note card. He stored these cards in one box. Then he thought about what he had read and its relevance to his work, recorded those thoughts on other cards, and stored them in a second slip box. These cards were atomic units of thought: one idea per card. Each note included a unique identifier.
When writing a note, Luhmann thought about what was already in his slip box. He drew links between the new note and the old ones, connecting them through the identifier. In this way he developed chains of ideas and arguments.
Schmidt suggests the essential characteristics of Luhmann's system were a specific organization and card integration based on rules of numbering, an internal system of linking, and a comprehensive keyword index. Schmidt adds that Luhmann used three kinds of links:
- References in the context of a larger structural outline (similar to a table of contents, an outline or a map of content).
- A subject-area index of references (similar to a tag).
- Individual references from one note to another (similar to a related link).
Effective linking matters, because without links a note is easy to lose.
Luhmann described his zettelkasten as a conversation partner and thought partner. He valued its ability to provoke surprise and surface novel connections. It produced knowledge by putting ideas into contact that one might not otherwise have connected. He also understood that an idea recorded at one point in time may not become valuable until it is connected to another, future idea (Schmidt).
2The purpose of a zettelkasten
The purpose of a zettelkasten is to facilitate thinking. Storing notes is only the first step, and treating the box as an archive invites the collector's fallacy. A well-maintained zettelkasten works as a thinking tool. It provokes new ideas by bringing disparate sources into conversation with one another and with the researcher. It frees the brain from remembering dry facts, so the brain can spend its effort on the more important work of generating new insight.
The zettelkasten was a constant source of ideas and inspiration, so Luhmann never needed to rely on brainstorming or other idea generation tactics. It was a productivity system, a method for producing insight. As the zettelkasten grew, so did its capacity to create new knowledge.
3Kinds of notes
In the method as Ahrens describes it in How to Take Smart Notes, there are three kinds of notes:
- Fleeting notes, captured while reading or consuming a source, which serve as reminders of information. They can usually be trashed before too long.
- Permanent notes, written so that they are perfectly legible apart from their original context, as if they were ready for print.
- Project notes, which pertain to a specific project and are disposable once the project is complete.
Some approaches to the zettelkasten add "literature notes", a phase between fleeting and permanent notes. It is unclear whether Ahrens sees these as distinct from permanent notes in his taxonomy.
One rule runs through all the types. Never copy notes verbatim. Rephrasing an idea creates an immediate feedback loop: you have to wrestle with the idea and understand it well enough to say it in a new way. The reasoning is in Make notes in your own words.
3.1Fleeting notes are reminders
Fleeting notes, as Ahrens describes them, are the scraps of notes we should habitually take while reading or thinking, using some ubiquitous capture method (digital or analog). They are the raw material of ideas. On their own they serve little purpose beyond acting as reminders.
Put them in an inbox to process later, but not too much later. If too much time passes between capturing a fleeting note and processing it, you may forget the information you wanted to keep.
Do not copy fleeting notes verbatim. Translating them into other words helps you understand the content, whereas copying a quotation word for word can alter its meaning by ripping it out of its context (see Writing is thinking).
Highlighting or underlining passages in a book and writing marginalia are all kinds of fleeting notes. Because fleeting notes are reminders, you can trash them after processing.
3.2Literature notes inform permanent notes
Literature notes record anything from a text that you might want to use later. They should reflect the work you are consuming accurately and faithfully, while translating the ideas into new words to support understanding.
Be selective when you make them. The collector's fallacy tricks us into thinking that because we captured information, we mastered it.
Always write literature notes with the notes you have already taken in mind, and with an eye toward creating new permanent notes.
3.3Permanent notes stay useful, not unchanging
There is much confusion between permanent and literature notes in the zettelkasten world. On the zettelkasten.de forum, user @Will offers his take: permanent notes are permanently useful, and that does not depend on the source or on the originality of the content. Permanent notes carry no special appointment. A more productive reading of "permanent" is "permanently useful".
Notes are not carved in stone. They change, evolve, mutate, flex, adapt, shrink and grow. As Schmidt points out, Luhmann did not wait to "develop the idea to maximum sophistication" before adding it to his zettelkasten. The usefulness of an idea may only become apparent much later, when it relates to an idea that has not arrived yet.
3.4Project notes
Project notes belong to one project, so they are disposable once that project is complete.
4Surprise and randomness
4.1Surprising connections make learning stick
Information is created by juxtaposing one idea with another. Insight emerges when that juxtaposition creates a sense of surprise. When we are confronted with a novel perspective instead of the expected message, it expands our understanding by provoking comparison and contrast, evaluation and re-imagination.
For this reason it is good to read broadly, and to build information systems that include an element of randomness. Schmidt points out that Luhmann's zettelkasten created new knowledge by systematically connecting ideas that have no obvious connection to one another.
4.2Add randomness to surface unexpected connections
It is tempting to structure our knowledge systematically, but this has pitfalls. Systematizing forces decisions early on, and those decisions may confine us to narrow lanes of inquiry. We then meet less novel information and fewer unexpected connections.
It is better to build the possibility of randomness into a knowledge management system. Create systems and workflows that can surprise us with unexpected connections between ideas. Luhmann describes these as "combinatorial possibilities which were never planned, never preconceived, or conceived in this way." They give us more chances at creativity and new insights, and they counter our bias toward information that is more available or more familiar to us.
5Related notes
- ideas-are-constellations
- fostering-serendipity
- novel-metaphors-create-novel-ways-of-thinking
- Brainstorming surfaces available ideas, not new ideas
- Decontextualize ideas to make them new
6Citations
- Ahrens, Sönke. How to Take Smart Notes: One Simple Technique to Boost Writing, Learning and Thinking - for Students, Academics and Nonfiction Book Writers. Sönke Ahrens, 2017.
- Luhmann, Niklas. "Communicating with Slip Boxes." Translated by Manfred Kuehn. Two Essays by Niklas Luhmann. Accessed October 19, 2020. https://luhmann.surge.sh/communicating-with-slip-boxes.
- Luhmann, Niklas. "Learning How to Read." Translated by Manfred Kuehn. Two Essays by Niklas Luhmann. Accessed October 27, 2020. https://luhmann.surge.sh/learning-how-to-read.
- Schmidt, Johannes F. K. "Niklas Luhmann's Card Index: The Fabrication of Serendipity." Sociologica 12, no. 1 (2018): 53-60.
- @Will. "All Notes Are Malleable: Strive for Permanently Useful Notes, Not Permanently Unchanging Notes." Zettelkasten Method (blog). Accessed October 21, 2020. https://www.zettelkasten.de/posts/literature-notes-vs-permanent-notes/.
Adapted from David Drysdale's Moby Diction notes.