2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/150710The story of (Ward-)Takahashi relations and their impact on physical theory is reviewed.11 pages, 1 figure, BoxedEPS, REVTeX; email to jackiw@mitlns.mit.eduHigh Energy Physics - TheoryGeneral Relativity and Quantum CosmologyHigh Energy Physics - PhenomenologyHistory and Philosophy of PhysicsQuantum Physicstext