It is common practice in intergenerational justice to set fixed thresholds determining what qualifies as justice. Static definitions of how much and what to save for future generations, however, overestimate human epistemological limits and predictive capacity in regard to uncertainty in social- and ecosystems. Long-term predictions cannot account for the inherent range of contingent variables at play, especially according to contemporary theories of punctuated equilibrium. It is argued that policies deliberately testing ecological limits as currently conceived must be excluded from (...) political calculations to minimize current actions from foreclosing future life quality and options. To better reduce harms to present and future generations and support the stability of just institutions (and the stable environments they depend on) as Rawls and others demand, polities can overcompensate resource allocation to environmental sustainability. Focus on reducing environmental harms benefits both current and future generations, reconciling distributive versus intergenerational justice trade-offs. (shrink)