Hedgehog reappears, loses to fox

Hedgehog reappears, loses to fox
International Journal of Epidemiology 2007; 36:3-10
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In a famous essay, Isaiah Berlin used a fragment from an ancient Greek poem to characterize '[O]ne of the deepest differences which divide writers and thinkers, and, it may be, human beings in general.' That fragment is: 'The fox knows many things, but the hedgehog knows one big thing.' He continued, [T]here exists a great chasm between those, on one side, who relate everything to a single central vision, one system less or more coherent or articulate, in terms of which they understand, think and feel ... and, on the other side, those who pursue many ends, often unrelated and even contradictory, connected, if at all, only in some de facto way ... The first kind of intellectual and artistic personality belongs to the hedgehogs, the second to the foxes.40 Hedgehogs are likely to think of prediction as a deductive exercise, whether based upon functionalism, free market economics or Marxism, whereas foxes are likely to make predictions based upon careful observations of particular cases. And studies of political forecasting indicate that foxes are better forecasters than hedgehogs, precisely because foxes are not committed to an overarching theory but are able to learn from their mistakes and remain open to new information. In a study of the forecasting accuracy of political experts, Philip Tetlock41 found that those who were least accurate looked very much like hedgehogs: '[T]hinkers who "know one big thing", aggressively extend the explanatory reach of that one big thing into new domains, display bristly impatience with those who "do not get it", and express considerable confidence that they are already pretty proficient forecasters, at least in the long term.'42 They are people who are likely to 'trivialize evidence that undercuts their preconceptions and to embrace evidence that reinforces their preconceptions.'43 Those who were more accurate 'look like foxes': [T]hinkers who know many small things (tricks of their trade), are skeptical of grand schemes, see explanation and prediction not as deductive exercises but rather as exercises in flexible 'ad hocery' that require stitching together diverse sources of information, and are rather diffident about their own forecasting  prowess, and ... rather dubious that the cloudlike subject of politics can by the object of a clocklike science.44 Foxes have a 'more balanced style of thinking about the world-a style of thought that elevates no thought above criticism.'45 Social epidemiology is more nearly akin to political forecasting than to physics. When considering the ssociations between sex, race and social roles on the one hand and health and disease on the other, accurate prediction is unlikely to rest upon deductive science and more likely to result from stitching together all that one can know about the context-institutional, cultural, political, epidemiological-in which particular populations live and work. Thus, social epidemiology is scientific as it reconstructs the past and explains the present, but it is not likely to be powerfully predictive. When it is successfully predictive, it is not likely to be because it is based upon deductions from scientifically valid generalizations that are true across time and place, but because analysts understand more or less intimately the people and places with which they are concerned, and because they can extrapolate sensibly from relevant experiences and groups elsewhere.