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Prof. Smil turns to diverse quantitative data as a way to transcend the biases that so often are part of the environmental movement. He notes that there are usually two camps: the catastrophists and the cornucopians (p. 35). However, the view today is more multi-faceted: the Planetary Boundaries concept involves 9 factors, some of which are stable and others aren't, instead of the old either-or scenario for development or conservation. Smil also has an interesting attitude towards time or history: in the same book he extensively uses historical data, trends, and charts, and then concludes that future projections are frequently inaccurate ("even our best simulations of long-term interactions among environmental, economic, technical and social developments have been simplistic and misleading. Biases have thus an enormous role in interpreting the past record and forecasting the future.", p. 35). Yet the tone of this book is not pessimistic. The author insists on realism, calling out successes and failures in ecology and energy as the scientific data and historical trends reveal. For example, while citing the success of China in stabilizing its population there is also slow progress in Africa and South Asia. "Nearly half of the world-wide population (3.2 billion people) forecast between 1990 and 2025 come in just six countries: India (almost 600 million people), China (350-400 million), Nigeria (150-180 million), Pakistan (close to 150 million) and Bangladesh (100-120 million)." (p. 173). There is much more that could be written about this book. The topics go from the macro to micro-scale resources and challenges. The author has especially good charts for visualizing data. There a chart that categorizes air pollution by "Transport Distance" and "Residence Time"; positive aspects of energy use and how it allows higher educational levels (p. 128-129); and power densities (p. 187, a topic which later became its own book). There is a good chapter about effective strategies, including reducing energy use (p. 142). In this title and others, Smil convincingly presents the case for energy conservation and efficiency. There are huge gains that can be made with vehicle, housing, water, and agricultural efficiency (note: "Buildings are either the largest or second largest consumers of energy (behind industries) in all rich countries", p. 143). On top of all this, Smil is an eloquent writer. He also gives ample credit to preceding and contemporary scientists and authors. There is good reason for the success of "Global Ecology".