“The third zone consists of the flat alluvial plain between the two rivers, the Euphrates and the Tigris. It comprises the ancient kingdom of Sumer in the south of the plain, and Akkad in the north, and according to tradition was the site of the Garden of Eden. Looking at it today it is hard to understand why this featureless waste, exposed to every extreme of heat, flood and storm, should ever have been identified with the original land of plenty and ease. Yet, in spite of its apparent inhospitality, the soil is immensely fertile, capable of producing a huge agricultural surplus which underpinned what is arguably the earliest civilisation in the world. The Sumerian civilisation is in many ways the classic example of the Toynbee theory of 'stimulus and response' or, in less academic terms, of necessity being the mother of invention. [...] It is not entirely frivolous to suggest that if the region had been more hospitable the Sumerian civilisation might not have developed as early as it did.”