Conflicting Messages From Weak and Strong Sustainability Metrics

ABSTRACT Weak and strong sustainability represent two opposing ways of understanding sustainability. This is reflected in the metrics used to monitor both types of sustainability, where the former favours monetary aggregates of manufactured, human, and natural capital, while the latter favours biophysical indicators. A comparison of the outcomes of weak and strong sustainability metrics leads to conflicting messages between the two paradigms when assessing sustainability status and trends. Weak sustainability metrics downplay the relevance of environmental degradation, arguing that in most countries economic development is sustainable or close to being sustainable. In contrast, strong sustainability metrics argue that the world and the vast majority of nations are unsustainable. There are, however, possibilities for creating shared narratives in which the biophysical insights provided by strong sustainability metrics are complemented with those from weak sustainability metrics. From this, we also identify opportunities to move towards more meaningful sustainability narratives that combine both perspectives.