Every influence event — a belief updating, an emotion shifting, an action being taken — is produced by one or more named mechanisms operating at specific levels of the predictive processing hierarchy. This taxonomy is the instrument panel for ROOT's branch architecture. Mechanisms are not techniques. They are the underlying operations that techniques instantiate. Understanding them at this level allows you to diagnose why copy works, predict what will work, and build sequences that are structurally valid rather than merely intuitive.
ROOT context: This taxonomy sits at the intersection of the Technique Registry and the Branch Sequencing Grammar. Each mechanism maps to one or more FE scoring dimensions (FE-A, FE-V, FE-E, FE-R, FE-C), a PP hierarchy level (L1–L6), and an inference mode (perceptual / active / transition). The full registry entries — with FE scores, viscosity match, field compatibility, and sequencing constraints — are built from these foundations. Mechanisms marked new were added from the extended source library. Mechanisms marked citeable have formal academic grounding.