How can a psychologist inform economics? The strange case of Sidney Siegel

Before Kahneman and Tversky showed how behavioural economics could bring psychology and economics into a unified framework, in the 1950s a social psychologist, Sidney Siegel, entered the realm of economics and laid the foundation of experimental economics. This paper gives an assessment of Siegel’s overall contribution and claims that Siegel was not only a pioneer of experimental economics but also of behavioural economics. Had his view on the integration of psychology and economics been more promptly received, it might have triggered a different and more successfully path to the injection of greater realism in economics. When Siegel died, his approach to integrate psychology and economics lost its main advocate. Although his legacy was paramount in the work of the Nobel Prize Vernon Smith, Siegel endorsed a quite different approach to how make interdisciplinary research effective.