The Price of Virtue : Some Hypotheses on How Tractability Has Shaped Economic Models

This paper seeks to convince historians that asking how tractability has shaped individual and collective modeling choices in economics is a worthy question. To do so, I first survey the economic methodology literature on tractability, one that grew out of methodologists’ attempts to dissect economic models and explain why their contributors make unrealistic assumptions. I then compare these accounts with the few instances where 20th century economists have discussed tractability openly, and I show that such historical survey, however short and incomplete, sheds light on features of tractability in need of further investigation. My claim is that historians could contribute by documenting the collective dynamics at work when tractability motives are invoked. I suggest that disentangling theoretical, empirical and computational tractability might be fruitful, but also difficult. I ask how and why choices made for tractability purpose, thus meant to be idiosyncratic and temporary, often become collectively entrenched, sometimes creating “tractability traps.” Finally, I consider the existence of “tractability standards” that differ across time and fields and document how they tie to specific concepts of solutions