What is signal detection theory?

Signal detection theory is a concept in personal epistemology: Instead of blocking noise, create systems that actively surface what matters.

Example: Your team's Slack workspace has 47 channels. One approach: mute 40 channels and hope the right information leaks through. Better approach: build a daily brief — a 10-minute ritual where you scan three specific channels for decisions, blockers, and shipped work. You stop trying to block noise and start detecting the three categories of signal that actually drive your week.

This concept is part of Phase 7 (Signal vs Noise) in the How to Think curriculum, which builds the epistemic infrastructure for signal vs noise.