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

This paper seeks to convince historians that investigating how tractability has shaped individual and collective modeling choices in economics is a valuable endeavor. To do so, I first survey the economic methodology literature on tractability, one that grew out of methodologists’ attempts to explain why their authors make unrealistic assumptions. I then compare these accounts with the few instances where 20th century economists discussed tractability explicitly. This short survey suggests that there is a need for historians to document 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 purposes 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.