CONCEPT
Redundancy Principle
The safety-engineering doctrine — central to Perrow's framework — that systems operating in the dangerous quadrant require diverse independent backups, and that the defense against common-mode failure is independence, not duplication.
Redundancy is the primary defense against the unanticipated failure modes that interactive complexity produces. If you cannot predict which specific failures will occur, you must build a system capable of absorbing many possible failures through backup capacity that can substitute for failed components. The critical qualifier is diverse: redundant systems that share the same vulnerability provide no real protection against that vulnerability. Two backup generators in the same basement flood together. Two AI tools trained on the same data produce correlated errors. The redundancy that matters is redundancy whose components do not share common modes — different training sets, different architectures, different vendors, different cognitive lineages.
In The You On AI Field Guide
Segal's decision in You On AI to maintain his engineering team at full size despite the twenty-fold productivity multiplier is, in Perrow's framework, a redundancy preservation decision. Whether Segal recognizes it or not, keeping more independent minds in the system than strict efficiency requires is the structural defense