From Cournot to Public Policy Evaluation: Paradoxes and Controversies of Quantification

prisme7Prisme N°7 April 2006

Alain Desrosières

Prisme N°7 April 2006 (258.2 KiB)


The French mathematician, economist and thinker Augustin Cournot inaugurated the philosophical treatment of the new probabilistic and quantitative modes of reasoning that emerged in the first half of the 19th century. The text reviews the legacy and implementation of Cournot’s intuitions concerning the distinction between so-called objective and subjective probabilities, and the interpretation of the categories constructed by statisticians according to “equivalence conventions”. Suggestive clues emerge for the empirical study of current statistical practices, in particular, those transactions that take place in the “contact zone”, where quantified assertions recorded in more or less formal models replace unquantified assertions formulated in natural language. Examples of these exchanges are illustrated in the cases of risk management, macroeconomic policy and public service performance evaluation.

In conclusion, the paper highlights how the ambivalence of Cournot’s thought is echoed in the controversies raised in some recent sociology of science, polarized between diverse forms of “realism” and “constructivism”. Questions suggested by Cournot are the starting point for an exploration of the sense in which quantification can be said to create objectivity.