On the survival of a flawed theory of capital: mainstream economics and the Cambridge capital controversies

The Cambridge controversies on capital theory opposed heterodox economists, mainly from the University of Cambridge, UK, to mainstream economists, mostly based at the Massachusetts Institute of Technology, Cambridge, USA. The controversies started in the 1950s and occupied the pages of some of the most influential journals. Their primary outcome was the broad acknowledgement of flaws, which we retrieve, in the concept of aggregate capital. Despite that acknowledgement, aggregate, homogeneous capital remains a staple of contemporary macroeconomics, as if the Cambridge controversies had never existed. To account for this apparent paradox is the aim of this article. We examine the arguments seeking to justify the enduring commitment to the aggregate capital approach and argue that they indicate an implicit commitment to instrumentalism. The indifference to the results of the Cambridge controversies is a consequence of methodological conformism and has shaky foundations.