Don’t leave it to the economists! - Adam Hayes, Irrational Together: The Social Forces That Invisibly Shape Our Economic Behavior, University of Chicago Press, 2025

Surely not another book on behavioural economics?Several Nobel prizes have been awarded to pioneers in this field, which is itself at least fifty years old now.Finance journals are flooded with kilometres of articles dedicated to outlining new manifestations or nuances related to prospect theory or the disposition effect.Is there really much more we can learn about the forces that drive us to make rational and irrational decisions?Yes, is the short answer to that question, although this does not imply more behavioural economics so much as an expanded intellectual paradigm.In order to understand economic behaviour more comprehensively, we need to think beyond the obsession with purely cognitive bias and the rather bizarre reliance on using WEIRD (Western, Educated, Industrialised, Rich, Democratic) MBA students as cannon fodder for experimental studies.Instead, we need to embrace the cultural and social factors that shape our economic action.Refreshingly, this is something that even behavioural economists themselves have started to recognise.For example, David Hirshleifer (2015: 44) has argued that behavioural economics needs to 'draw on social psychology and sociology as well as cognitive psychology and decision theory, and will require focused attention to the microstructure of social transactions'.Hirshleifer calls this new paradigm of thought 'social finance'.In his presidential address to the American Finance Association, social finance was hailed by its progenitor as a 'once in a generation research opportunity' and 'a new way to understand human behavior' (Hirshleifer, 2020(Hirshleifer, : 1817)).This is all well and good, but the last thing we probably want is economists who have merely read Nudge (Thaler and Sunstein, 2009), Thinking Fast and Slow (Kahneman, 2011), or Cognitive Psychology for Dummies (Hills and Pake, 2016) to start telling us how society works.One of the main problems with intellectual approaches dominated by economics is that they are anthropologically ignorant (Bourdieu, 2005).Supplementing economics with a smattering of cognitive psychology will only take us so far.Instead, does it not make more sense to draw on expertise from the wider social sciences to make sense of the things that economics and cognitive psychology alone simply cannot?Mercifully, this is what Adam Hayes does in his latest book, Irrational Together (2025).Drawing from wider sociological framings that cleverly meld Weber, Bourdieu, Zelizer, Mauss, Durkheim, Callon, and others, Hayes systematically and convincingly draws attention to various areas of economic activity that simply cannot be adequately explained by behavioural economics.What we are treated to is a book about economic behaviour that significantly exceeds the bounds of behavioural economics.This is important work, both academically and for shaping popular understandings of economic behaviour.The book itself is wide ranging and draws from examples as diverse as an interchange on tipping from the HBO show Curb Your Enthusiasm through to more academic empirical work looking at how Haredi Jews in Israel divide economic roles in the household.