Debreu ’ s apologies for mathematical economics after 1983

When reassessing the role of Debreu’s axiomatic method in economics, one has to explain both its success and unpopularity; one has to explain the “bright shadow” Debreu cast on the discipline: sheltering, threatening, and difficult to pin down. Debreu himself did not expect to have such an influence. Before he received the Bank of Sweden Prize in 1983 he had never openly engaged with the methodology or politics of mathematical economics. When in several speeches he later rigorously distinguished mathematical form from economic content and claimed this as the virtue of mathematical economics, he did both: he defended mathematical reasoning against the theoretical innovations since the 1970s and expressed remorse for having promised too much because it cannot support claims about economic content. The analysis of this twofold role of Debreu’s axiomatic method raises issues of the social and political responsibility of economists over and above standard epistemic issues.