What does it mean that clusters in your graph reveal your domains?

Natural groupings in your knowledge graph show you what you know most about.

Example: You've been building a knowledge graph for two years. You never created a category called 'decision-making under uncertainty.' But when you look at your graph's structure, thirty-seven notes about cognitive biases, probabilistic reasoning, pre-mortems, and Bayesian updating form a tight cluster with dense internal links. The graph is telling you something your filing system never did: this is a domain you've been building expertise in, whether you planned to or not.

Try this: Open your note system's graph view (or export your links and sketch them). Identify the three densest clusters — groups of notes that link heavily to each other but less to the rest of the graph. For each cluster, write a one-sentence label describing what that cluster is about. Now compare those labels to whatever categories, folders, or tags you originally created. Where do they match? Where do the clusters reveal a domain you never formally named?