4 Externalities, Resilience, Vulnerability, Emergence, Agency, Scales, and Boundaries

Understanding Externalities

Externalities are costs or benefits of an economic activity that affect third parties and are not reflected in the market price. In sustainability, negative externalities like pollution or resource depletion often go unaccounted for, leading to unsustainable practices.

For example, a factory emitting pollution may create a negative externality by harming public health, yet the costs of that harm are not borne by the factory. Addressing these externalities is a key challenge in sustainability because it requires systems thinking to trace unintended consequences across various interconnected systems.

Resilience and Vulnerability in Systems

• Resilience is a system’s ability to absorb disturbances and still function. A resilient system can adapt to changes and continue to provide essential services.
• Vulnerability refers to the susceptibility of a system to harm from external shocks. Systems with less diversity or redundancy are often more vulnerable to disruptions, whether from environmental changes or social and economic upheavals.

Resilient systems often include multiple pathways to achieve goals, meaning that if one path fails, others can compensate. For example, a diverse agricultural system with multiple crop varieties is more resilient to climate changes than one that relies on a single crop.

Emergence and Agency

• Emergence refers to new properties or behaviors that arise from the interactions of a system’s parts. For example, ecosystems often develop balance and harmony despite the competitive behaviors of individual species.
• Agency is the capacity of individuals or entities within a system to act and make decisions. In sustainability, the agency of individuals, organizations, and governments can determine whether systems are managed sustainably.

Scales and Boundaries in Systems Thinking

Systems operate at different scales, from local to global, and understanding the scale at which a problem exists is crucial for identifying appropriate solutions. For example, local air pollution may require municipal regulations, while global climate change requires international cooperation.

Boundaries define the limits of a system—both physical and conceptual. For example, when addressing water use, it’s essential to define whether you’re looking at a local watershed or the global water cycle.