An Economist Takes on the Parable of the Good Samaritan

Who will help those in less-fortunate situations when everyone believes that someone else will do the job? This is the question that Ted Bergstrom addresses in a new paper published in the American Economic Journal: Microeconomics entitled: “The Good Samaritan and Traffic on the Road to Jericho“.

Bergstrom illustrates his paper with a modern retelling of The Parable of the Good Samaritan (Luke 10:25-37):

Driving along a lonely road, you come upon a stalled car and a motorist who appears to have run out of gas. You consider stopping to offer help, although this may cost you several minutes and some extra driving. Would your decision be different if the road were more heavily traveled? If you were to run out of gas, would you prefer that it be a busy street or a lonely road?

The paper presents the decision to stop and help as determined by an agent’s economic cost of stoping and helping, the psychic cost (noted as either sympathy or empathy), and the duration of time the stranded motorist must wait before being helped. I’ll save the “elegance” of the model for the curious reader to look up in the actual paper. The theoretical model provides two insights.

(1) If everyone has the same ratio of economic costs to psychic costs, as traffic becomes more frequent the equilibrium probability that any individual will help decreases, but the expected wait time for the stranded traveler remains constant.

(2) If people have different ratios of economic costs to psychic costs (this is… erm… more likely), as traffic becomes more frequent the equilibrium probability any individual will help again decreases, but the expected wait time for the stranded traveler now also decreases.

This is an interesting and fun paper for several reasons. First, this is a Biblical parable that has been retold as a game theoretic fable. As was the case when this parable was originally told, taken literally, this parable has a relatively narrow application. Both Luke’s transcription of the parable and Bergstrom’s retelling, however, provide new insights into how the world works and allow for fresh thinking about many situations.

Second, this paper presents an economic model, with actual real-world application, that includes the concept of empathy as an integral factor in the framework. (Actually, the paper repeatedly uses the term sympathy, but I think the concept being modeled is empathy.) Indeed, encountering an economic model including either concept of sympathy or empathy is rare these days. These two concepts are importantly distinct, and if I were to have one critique of this paper it would be that it should have been more clear about whether it is modeling sympathy or empathy.

Sympathy is a feeling of sorrow or pity for someone else, whereas empathy is the ability to understand and see one’s own self within others. It seems to me a lot of people have sympathy for other’s who are in less-fortunate situations. Empathy, however, requires an additional step: that one recognizes that they themselves could just as likely find themselves in the same less-fortunate situation. Anyway, I’m excited to see economists include these concepts in their models, but we need to be thoughful with how we use these concepts to accurately describe our ideas.

Finally, I think there is a worthwhile theological or hermeneutical discussion of the results of this paper. Bergstrom writes, “Perhaps the priest and the Levite who hurried past the injured traveler had good excuses. Maybe they had important things to do and realized that if they did not stop, someone less busy would soon be likely to appear and perform the rescue”.

This is a fine comment in the context of the theoretical model, but I think it sells the parable short theologically. Sure, perhaps the priest and the Levite thought someone else would come along on the (busy) road to Jericho and help the injured traveler, but they would have never expected that a Samaritan would stop. At the time, the stereotype of Samaritans was that they were stingy and generally bad people. The priest and the Levite, however, were supposed to be the total opposite: kind and generally nice people. In the parable not only does the Samaritan stop to help the injured traveler, but he paid for the traveler’s stay at a local inn with two denarii (which was worth roughly two days wages). So in terms of the model developed by Bergstrom, the Samaritan had a low economic cost to empathy ratio. This caused him to stop. Meanwhile, the relatively high economic cost to empathy ratio of the priest and the Levite caused them to continue on their way. While Bergstrom’s model suggests we can’t necessarily blame the priest or the Levite for not stopping, this was not the culturally-imbedded interpretation at the time of the parable’s original telling.

The Parable of the Good Samaritan is told as a response to the question, “Who is my neighbor?” Indeed even today, many ask this question hoping for a response that some people are not. Instead this parable turns the question on it’s head. We are called to be a neighbor whenever we are needed and to recognize that neighbors can come from surprising places.