Convergent Nodes, Bifurcating Failure, and the Governance of the Committed Gate

Systems that fail are usually described lesion by lesion, as though each breach were its own private catastrophe. We argue instead that a large class of failures — economic, ecological, institutional, and physiological — express a single design: a committed node that converges several inputs and, when load exceeds capacity, does not degrade gracefully but bifurcates into two failure geometries. We specify these geometries, derive their type-specific kinetic early-warning markers, and identify the most rigorous biological exemplar of the architecture: a dual node that senses and actuates at once, tunable between geometries by a single parameter, and therefore the calibration case the theory required. We give the control surface its cusp normal form, derive the hysteresis window that follows, and state the observations that would refute the model. The exemplar is undignified. The mathematics is not. We offer this as a synthesis warranting investigation, and we ask the reader to hold the line until §2.