Collapse: How Societies Choose to Fail or Succeed  Collapse: How Societies Choose to Fail or Succeed (titled Collapse: How Societies Choose to Fail or Survive for the British edition) is a 2005 book by academic and popular science author Jared Diamond, in which the author first defines "collapse": "a drastic decrease in human population size and/or political/economic/social complexity, over a considerable area, for an extended time." He then reviews the causes of historical and pre-historical instances of societal collapse—particularly those involving significant influences from environmental changes, the effects of climate change, hostile neighbors, trade partners, and the society's response to the foregoing four challenges—and considers the success or failure different societies have had in coping with such threats. While the bulk of the book is concerned with the demise of these historical civilizations, Diamond also argues that humanity collectively faces, on a much larger scale, many of the same issues, with possibly catastrophic near-future consequences to many of the world's populations. In the prologue, Jared Diamond summarizes his methodology in one paragraph:  Diamond identifies five factors that contribute to collapse: climate change, hostile neighbours, collapse of essential trading partners, environmental problems, and the society's response to the foregoing four factors. The root problem in all but one of Diamond's factors leading to collapse is overpopulation relative to the practicable (as opposed to the ideal theoretical) carrying capacity of the environment. One environmental problem not related to overpopulation is the harmful effect of accidental or intentional introduction of non-native species to a region. Diamond also writes about cultural factors (values), such as the apparent reluctance of the Greenland Norse to eat fish. Diamond also states that "it would be absurd to claim that environmental damage must be a major factor in all collapses: the collapse of the Soviet Union is a modern counter-example, and the destruction of Carthage by Rome in 146 BC is an ancient one. It's obviously true that military or economic factors alone may suffice". He also lists twelve environmental problems facing humankind today. The first eight have historically contributed to the collapse of past societies:  Further, he says four new factors may contribute to the weakening and collapse of present and future societies:    Anthropogenic climate change  Buildup of toxins in the environment  Energy shortages  Full human use of the Earth’s photosynthetic capacity   In the last chapter, he discusses environmental problems facing modern societies and addresses objections that are often given to dismiss the importance of environmental problems (section "One-liner objections").