What is cognitive inertia?

Cognitive inertia is a concept in personal epistemology: Established schemas persist even when contradicted by evidence.

Example: You learn that a colleague you've judged as 'uncommitted' has been working 60-hour weeks on a project you didn't know about. Your immediate reaction isn't to update the schema. It's to explain it away: 'They're probably just catching up on things they dropped.' The evidence is right there. But the schema was there first, and it fights to stay.

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