We define stability as the resiliency, robustness, and constancy of our nested social, financial, and environmental systems. Stability is the degree to which our systems can withstand stress and maintain their functionality over time.
Why do we need stability? All else equal, a stable society is preferable to an unstable society. Stability - the product of the harmonious interaction between parts, or interwoven systems - protects against uncertainty and decay. For example, a healthy body regulates its blood glucose levels to provide cells with their required energy. Too much glucose makes cells sticky, with a paralyzing effect. Too little glucose starves them. What's important is the constancy of glucose regulation within functional limits, and the resiliency to maintain this regulation amidst adversity.
Instability occurs when systems transgress functional limits, causing the breakdown of other systems and suffering for those who depend on them. When interlocking systems remain stable, they provide a fertile foundation for positive expectations that fuel investments in progress and broad cooperation throughout society.