What is Matthew effect?

Matthew effect is a concept in personal epistemology: Some loops reinforce themselves — success breeds more success or failure breeds more failure.

Example: A developer writes a useful open-source library. Downloads attract contributors. Contributors improve the library. The improved library attracts more downloads. Within two years, a weekend project has become critical infrastructure — not because it was inherently superior on day one, but because a reinforcing loop converted a small initial advantage into an insurmountable one.

This concept is part of Phase 24 (Feedback Loops) in the How to Think curriculum, which builds the epistemic infrastructure for feedback loops.