**1. Introduction**

While sustainability may be a relatively modern concept, attempts to understand the proper relationship between humanity and nature date back at least to ancient Rome and Greece. Unlike the modern world where science, religion, and philosophy tend to be discrete subjects with their own, distinct views on ecology, in the ancient Mediterranean these subjects were understood and studied together. As a result, ancient Greco-Roman thinking on sustainability and ecology was informed by a unique intersection of religion and science. For ancient Greek thinkers like Plato and Aristotle, for example, understandings of the natural world were part and parcel of a broader, philosophical exploration of both the nature of humanity and the nature of divinity. To understand whether nature was divine, for example, had important ramifications for understanding not only how nature operated scientifically but also how we should interact with other plant and animal species. For ancient Greco-Roman thinkers, the ethics of sustainability were inseparable from their metaphysics.

Ancient views on the metaphysical relationship between sustainability, ecology, religion, and science were not uniform, however. Key differences can be found not only in general metaphysical perspectives but specific views on ecology, such as around the notion of extinction. Some of our earliest thinkers such as Aristotle believed that extinction was impossible because creation was divinely ordained and largely outside the purview of human activity. But other thinkers, particularly from the school of philosophy Stoicism, diverged from Aristotle in understanding extinction as a terrible, irreversible event. In both cases, metaphysics similarly underpins views on sustainability, but different views on sustainability arise as a result of different metaphysical assumptions and understandings.

The same is true in modern thinking, from the Renaissance onward. In many ways, influential thinkers on modern ecology such as Alexander von Humboldt and Charles Darwin replicate the same debates around sustainability and ecology we find in ancient thought. Like the debates in Greco-Roman thought, key differences in metaphysical understandings of nature explain differing views on ecological topics such as extinction and humanity's ethical obligation regarding sustainability. By exploring and comparing a variety of historical periods' views on the intersection of sustainability, ecology, religion, and science, we can identify how our own metaphysical understandings and assumptions today can lead to a more ecologically sustainable future.
