Where Does the Concept of "System" Become Non-Redundant, and Is Its Operational Shape Specific to Philosophy? Intervals of System-Concept Formation, Reciprocal Constraint, Return, Reconfiguration, and Dissolution across Philosophy, Science, Life, and AI

“System” is one of the most portable concepts across philosophy, science, biology, and AI. But if almost any sufficiently connected arrangement can be redescribed as a system, when does the concept itself perform non-redundant work? This paper begins by withholding the concept of system. It then introduces it independently and asks whether doing so changes discrimination, prediction, intervention, inferential dependency, return, or reconfiguration under matched conditions. If no additional operational difference appears, the system concept is redundant in that interval. The argument moves from Hegel, Schelling, Sellars, and Simondon to general systems theory, systems biology, and contemporary AI. It rejects both the assumption that systematicity is specific to philosophy and the opposite assumption that philosophy, life, science, and AI instantiate one universal systematic form. Controlled computational experiments test matched-budget representations, blind structure discovery, higher-order interactions, history dependence, and intervention-shift generalization. The results deliberately include configurations in which relational or historical representations lose rather than win. A real-text Hegel pilot examines systematic placement at §§15, 244, and 376/381 of the Encyclopaedia, while external validation protocols are fixed in advance for biological perturbation data, multi-agent trajectories, and independent Hegelian transition analysis. The central claim is methodological: a system concept that cannot lose cannot discriminate. “System” becomes significant only within configurations where its introduction performs non-redundant work and where conditions for its own dissolution can be specified.