Scale and Contingency

Since the early 1990s, the idea of contingency has been an important component of certain kinds of historical explanation. Following Stephen Jay Gould, who popularized the use of the word, “contingent” has two distinct meanings, glossing both “unpredictable” and “sensitive to initial conditions.” Use of the idea has not been rigorous in historical writing; it often serves as a black-box explanation for changes that we can’t otherwise explain or even as a narrative device that allows us to avoid vexed questions of causation.

In these remarks, I would like to reflect on the relationship between contingency and the scale of historical analysis. Historical explanations or arguments, typically, are particular to the orders in which they operate and cannot travel between the macro-level and the micro-level. We take it for granted, for example, that the explanation for a given homicide lies in contingent biographical circumstances whereas the explanation for the law-like regularities in changing homicide rates over time should be sought at a different scale. Extrapolating from this, it would appear that contingency describes a form of change that is detectable only at small scales. But this is not the case. Recent work on ideas of emergence, novelty, and innovation in fields such as paleontology offers frameworks that have made it possible for historians to deploy the concept of contingency for macro-level explanation. This use of contingency is essential for developing deep historical understandings that operate on large time scales.