Perrow's 1984 Normal Accident Theory holds that any system combining tight coupling with complex interactivity will inevitably produce catastrophic accidents

normal-accident-theorycharles-perrowsociology-of-technologytight-couplingai-safetyfirst-encounter-termunverified-secondary-citation

Charles Perrow's 1984 book Normal Accidents, written substantially in response to the 1979 Three Mile Island partial meltdown, argues that certain systems are structurally destined to fail catastrophically regardless of operator skill or safety engineering. The mechanism is the combination of two properties: tight coupling (processes proceed quickly, with little slack, so a disturbance in one part propagates before it can be caught or isolated) and complex interactivity (components interact in nonlinear, not-fully-visible ways, so operators cannot reliably predict how a local fault will cascade). Under Perrow's theory, a system with both properties will experience what he calls a "normal accident" — not an aberration to be engineered away, but a structurally inevitable outcome of the system's own architecture.

John Law's 2011 retrospective applies this framework to Fukushima, and Williams & Yampolskiy (2021/2024, arXiv:2104.12582) build an AI-failure-risk framework directly on it, arguing that rising AI system complexity and autonomy increases the likelihood of "normal accidents" by the same logic Perrow described for nuclear plants.

The note is flagged [unverified-secondary-citation — Perrow's 1984 book itself unread; the characterization above is Williams & Yampolskiy's summary]; see question-verify-perrow-1984-normal-accidents-primary-read.