# Requisite Variety **Domain:** Cybernetics / Complexity / Regulation **Doc Type:** Foundational Concept Node **Maturity:** Developing **Related:** [[Regulator Variety]], [[Variance Suppression]], [[Complex Adaptive Systems]], [[Russia and Prussia Kybernetiks]] --- ## Definition [[W. Ross Ashby|W. Ross Ashby’s]] principle that effective regulation requires sufficient response variety to absorb the variety of disturbances that matter to the controlled outcome. ## Kybernetiks Context [[Russia and Prussia Kybernetiks]] uses the law to explain standardization as a historical bandwidth workaround: states reduced learner variety because their regulators could not match it. ## Backlinks [[Russia and Prussia Kybernetiks]] · [[articles/Russia and Prussia Kybernetiks|Russia and Prussia Kybernetiks]]