I have always been interested in environmental aspects of human society, and I have published on food riots and the various societal mechanisms that were devised to cope with harvest shocks and the limitations of market channels. However, it was the grand narratives that linked the rise and fall of the Roman Empire – and in particular the positive response outside history with which these ideas were widely met – that involved me in the academic debate on this issue. I felt the need to engage in the debate, as historians who are sceptical of grand narratives are denounced as intuitively rejecting the role of environmental factors in human history.