Being and Gaia

This dissertation is grounded in a detailed analysis of Paul Tillich's ontology and theology, which allows me to develop a conceptual analysis grounded in a particular ontological theory. Specifically, that theory is the existential ontology developed by Martin Heidegger and theologically codified by Paul Tillich. Based in that analysis, the dissertation develops a philosophical concept of Nature, arguing that the modern understanding of Nature is a product of existential estrangement, the mechanistic understanding of nature of the seventeenth-century scientific revolution, and the technological drive to master nature. The modern concept of Nature is thus deeply ambiguous: Nature is that from which we are apart but simultaneously that of which we are a part. The dissertation then employs Tillich's method of correlation to correlate this concept of Nature with the recently revitalized symbolic name, Gaia, understood through the lens of James Lovelock's Gaia theory. This allows for a religious ethic of environmental conservation -- fully grounded in a scientific, ecological understanding of the life process of the Earth as a whole as well as a systematic and developed philosophical ontology and theology -- guided by the imaginative resource of an image of a living Earth, Gaia.