The Last Eighty Years: Continuities and Change

the first time Paul demeny asked me to write for PDR was in 1985 in a taxi in (as it was) west Berlin, going to a dahlem Conference on resources and world development. at that time i was still spending about half of my time working on China, and so i wrote an article on the country’s much-improved food supply. during the nearly three decades that followed, it was Paul’s repeated nudging that led me to ask ‘’what next?’’ and so i wrote (always given a much-appreciated free range) about diet and heart disease, planetary warming, how many people the earth can feed, environmental services, the nitrogen cycle and global population, eating meat, global catastrophic events, national socioeconomic and strategic trends, and harvesting the biosphere. after so many different topics for PDR, i was not immediately sure what the present essay should be about. eventually i proposed a topic, but then i decided to do something different, something obvious: to look back at the last eight decades in order to appraise the true nature of human advances and to emphasize our continuing inability to foresee fundamental changes. looking 80 years ahead did not tempt me at all because all truly longrange predictions are nothing but fairy tales, and hence must inevitably draw on an imagination that invariably tends to be either too feeble or too ridiculous. looking back is actually one of the best ways to make clear the futility of looking far ahead: when such efforts are seen in retrospect, they seem forced, naïve, awkward, and, above all, wide of the mark in their inevitably prejudiced selectivity and (often risible) bias reflecting the changing concerns of the day (as global warming displaces acid rain and as economic crisis displaces global warming) and the herd instinct of learned prognosticators. Growing frequency of forecasting and scenario-writing (by self-appointed experts, by think tanks of every leaning and consultancies, and by governments and corporations) might be seen as a proof that such products offer real insights and valuable guidance. But even a brief reflection dispels that impression. evolution of human societies is marked by continually and gradually un-