What is zettelkasten method personal knowledge management?

Zettelkasten method personal knowledge management is a concept in personal epistemology: Atomic notes with links between them create a growing network of processed knowledge.

Example: You read a book on decision-making under uncertainty. Instead of highlighting passages and moving on, you create three separate notes — one on the distinction between risk and uncertainty, one on the recognition-primed decision model, and one on how base rates improve probabilistic judgment. Each note is written entirely in your own words, captures exactly one idea, and is linked to related notes already in your system. The note on base rates links to an older note you wrote about Kahneman's anchoring bias. The note on recognition-primed decisions links to your note on expert intuition from a different book. The note on risk versus uncertainty links to your note on information asymmetry from an economics article. None of these connections existed in the original book. They emerged because your system forced you to ask, for every new idea: what does this connect to? Six months later, you are preparing a brief on how your team should evaluate a new market opportunity. You open your note on risk versus uncertainty, follow the link to information asymmetry, follow another link to base rates, and within ten minutes you have assembled an analytical framework that draws on four different sources you read over the past year. You did not search for these connections. The network surfaced them. That is the Zettelkasten working.

This concept is part of Phase 43 (Information Processing) in the How to Think curriculum, which builds the epistemic infrastructure for information processing.