What is circadian rhythm productivity?

Circadian rhythm productivity is a concept in personal epistemology: Using specific times or time intervals as triggers leverages your existing time awareness.

Example: You decide that every weekday at 7:00 AM, before checking email, you spend ten minutes reviewing your personal knowledge graph. Within a week, the alarm itself disappears from conscious awareness — 7:00 AM simply means review time. The temporal cue has become infrastructure. You no longer decide whether to review; you decide what to review.

This concept is part of Phase 22 (Trigger Design) in the How to Think curriculum, which builds the epistemic infrastructure for trigger design.