What is biological rhythms?

Biological rhythms is a concept in personal epistemology: Many personal patterns follow weekly, monthly, or seasonal cycles that become invisible when you only think in linear time.

Example: Every January you sign up for a new productivity system. Every March you abandon it. Every June you feel a surge of creative ambition. Every November you question your career. You've done this for eight years, but because you think in linear time — 'this year will be different' — you never notice the cycle. Plot your journal entries by month. The pattern is not subtle.

This concept is part of Phase 6 (Pattern Recognition) in the How to Think curriculum, which builds the epistemic infrastructure for pattern recognition.