Ideas about the basic nature of the universe are often implicit in our thinking and thus, in the manner of water to a fish, hard to appreciate. But what we think about the size and shape of the cosmos and about the nature of causation in the world around us – what there is, who is there and how it ‘works’ – permeates whatever we may come to think about anything else. Our cosmology will affect how we live in the world in deep and varied ways.

By “cosmos” I mean the nature of reality in its full extent and depth. A people's understanding of the cosmos, their cosmology, is their basic picture of the world, their most general or fundamental understanding of the overall structure of the universe (Smith 1995). This is very similar to what others have called “worldview.” Many of us view cosmology as a scientific matter. It is thanks to scientific research that the universe our minds now inhabit is profoundly different from that of any human even a century ago. It was only in the 20th century, to take just a few of the more transformative examples, that galaxies were discovered, that we realized the universe is more than a few million years old and expanding, that DNA is a key to inheritance and that there are inevitable – not just technical – limits to what it is possible to know. The 1856 discovery of a skull in Germany's Neander Valley, along with the work of people like Lyell and Darwin needed to appreciate it, set in motion an equally dramatic revision of how we understand our own coming into being.