What is eisenhower priority matrix?

Eisenhower priority matrix is a concept in personal epistemology: Classify tasks by urgency and importance to determine what to do, delegate, or delete.

Example: You sit down Monday morning to a list of 23 items. A client wants a revised proposal by noon (urgent + important). You have been meaning to restructure your note system for weeks (important, not urgent). A colleague pinged you to review a doc that could wait until Thursday (urgent-feeling, not important). And there is a recurring meeting you attend out of habit that produces nothing (neither). Without a classification system you treat all 23 items as equally demanding and let the loudest ones win. With the matrix you do the proposal, schedule two hours Wednesday for the note system, forward the doc review to someone closer to the project, and decline the meeting. Four decisions, twenty seconds each, and your week changes shape.

This concept is part of Phase 35 (Priority Systems) in the How to Think curriculum, which builds the epistemic infrastructure for priority systems.