A Stone Age hunter who worked out how to bring down two mammoths instead of one had improved his lot. A hunter who worked out how to stampede a whole herd over a cliff had wrecked his own food supply. Ronald Wright calls that second move a progress trap, and he spends five lectures on how often people have walked into one.

Wright gave these talks as the 2004 Massey Lectures, five speeches delivered in five Canadian cities and broadcast on the CBC Radio program Ideas, with House of Anansi Press publishing the book version the same year. His subject is societal collapse, read from what people left behind. Wright treats the ruins standing in deserts and jungles as headstones for civilisations that their own success undid, and he argues that the load the twentieth century placed on the planet follows a pattern as old as civilisation itself. By his account the modern predicament repeats something very old.

The lecture form shapes the reading. Wright has five sittings to make his case, so he moves at speed and puts every piece of archaeology to work for the argument, leaving out the apparatus a full scholarly history would carry. Canadian readers kept the book on bestseller lists for more than a year; it won the Canadian Book Association's Libris Award for Non-Fiction Book of the Year and took a nomination for British Columbia's National Award for Canadian Non-Fiction. Later printings added illustrations.