What is knowledge structures?

Knowledge structures is a concept in personal epistemology: A schema is a mental model that has been externalized, named, and structured so it can be examined, tested, and improved — turning invisible cognitive habit into visible cognitive infrastructure.

Example: A product manager navigates every prioritization meeting using an implicit mental model: 'urgent customer complaints always outweigh long-term roadmap items.' She has never written this down. She does not call it a rule. But it governs every decision she makes. The moment she writes it on a whiteboard — 'My prioritization schema: reactive customer pain > proactive roadmap investment' — it becomes an object she can inspect. Is this always true? Under what conditions should the roadmap win? What evidence supports this weighting? The mental model existed before. The schema exists now — explicit, testable, improvable.

This concept is part of Phase 11 (Schema Foundations) in the How to Think curriculum, which builds the epistemic infrastructure for schema foundations.