{'fraction_non_alphanumeric': 0.02007226013649137, 'fraction_numerical': 0.0008028904054596548, 'mean_word_length': 5.033898305084746, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 1, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Introduction: Population, Development and Human Natures

In Volume 3(4), EDE published a policy forum based on an article from the Economist, which carried the headline: ‘Forecasters of scarcity and doom are not only invariably wrong, they think that being wrong proves them right’. That forum contained the considered reactions of an eminent group of economists and scientists. It made the point that a kind of Heisenberg Principle operates in environmental predictions. The act of studying the problem itself affects the outcome by stimulating a reaction. Indeed, environmental predictions that do not ‘fail’ imply failure of the feedback mechanisms that are supposed to protect society from disaster. In this policy forum, two of the scientists who were the target of the Economist article argue the other side of the case, and a second eminent group of scientists offer their reactions to the argument. The forum is timely given the extraordinary publicity now surrounding the release of a book by Bjorn Lomborg that shares common purpose with the Economist article. What the reactions to the Ehrlichs’ paper show is the importance of investigating the effectiveness of feedback and response mechanisms in what is a very complex adaptive system. That is, after all, what lies behind scientists’ most frequently voiced concerns about human impacts on the environment. It is certainly what lies behind the Ehrlichs’ concerns in this paper. There is no merit in dismissing those concerns out of hand, or on the basis of the (necessary) inaccuracy of headline predictions about fundamentally uncertain processes. To be sure Kenneth Arrow, Elinor Ostrom, Tasos Xepapadeus, Ralph Hakkert, and Aart de Zeeuw are all the more optimistic about the capacity of the system to respond to information about impending environmental effects than are the Ehrlichs. But that optimism is based on an analysis of changes in social response mechanisms at multiple levels. Nor is it unqualified. Economists are most cautious in their assessment of the effectiveness of market mechanisms, and of institutional responsiveness than they were thirty years ago when they debunked the alarmist predictions of the ‘Club of Rome Report’. As their reactions to this forum show, feedback mechanisms have failed in the past and will continue to do so in the future. Indeed, improving both the feedback and the response mechanisms of the social system is a major challenge to the social sciences. The forum explains why.