Recovery, Reserve, and Hidden Viability Degradation: Can Future Loss of Viability Be Detected Before Current Function Fails?

This article develops the next empirical stage of Vitology by formalizing recovery, reserve, and hidden viability degradation as candidate predictors of future viability. The starting distinction is: current function ≠ remaining reserve ≠ recovery capacity ≠ future viability. A system may maintain its current critical function while its reserve decreases, its recovery becomes slower, its maintenance cost rises, or its space of future viable responses contracts. The article operationalizes the previously introduced concept of Hidden Viability Degradation as a condition in which observable present function remains approximately preserved while independently measurable determinants of subsequent viability deteriorate. A candidate Recovery–Reserve Profile is introduced: Π_RR(t) = {Rg(t), R(t), C_m(t), S_r(t)} where: Rg — domain-specific recovery characteristic; R — domain-specific remaining reserve; C_m — cost required to maintain current function; S_r — domain-specific sensitivity or response to standardized disturbance. The central empirical comparison remains the I0 Model A / Model B architecture: Model A_D = strongest domain-specific predictive model Model B_D = Model A_D + Φ_RRH where: Φ_RRH contains only prospectively defined Vitological information concerning recovery, reserve, and hidden degradation. Added predictive value is evaluated as: ΔP_RRH = P_B − P_A. Support for the I4 proposition requires reproducible improvement on independent data. Preserved current function alone is not interpreted as preserved viability, and deterioration of reserve or recovery is not automatically interpreted as a new Vitological regularity. The strongest possible result would be cross-domain reproduction of a structural relationship: disturbance → response → recovery → reserve change → hidden degradation profile → subsequent V while concrete mechanisms and measurement units remain domain-specific. I4 therefore tests whether the future loss of viability can sometimes become empirically detectable before visible failure of present function. Keywords Vitology; viability; recovery; reserve; resilience; hidden viability degradation; functional preservation; critical slowing down; physiological reserve; system degradation; maintenance cost; early-warning signals; viability trajectory; future viability; predictive value; Model A; Model B; cross-domain metrology.