Nudge theory’s popularity may block insights into improving society

Two scientists want their peers to dream big when it comes to changing societal behavior

a sign outside a bar reading 'a shot for a shot' with a picture of a vaccine needle, advertising a free drink for people who got a COVID-19 vaccine

In June 2021, a bar in Portland, Ore., offered people free alcohol if they got a COVID-19 vaccine. Such “nudges” have become a popular area of behavioral science research, but ignore larger questions, such as why people don't get vaccinated, two scientists argue.

John Rudoff/Sipa USA/AP Images

Imagine removing a branch of the U.S. government, say the Supreme Court. What are the myriad ways that such an upheaval might reshape people’s lives?

Policy makers and researchers probably would want to have an idea of what those effects might be before erasing the highest court in the land. But “you can’t test deep structural changes like that in an experiment” first, says behavioral decision–making expert David Gal of the University of Illinois Chicago.

headshot of behavioral scientist David Gal
Behavioral scientist David Gal would like to see his peers move beyond nudges to generate overarching theories that explain why people behave the way they do.Univ. of Illinois Chicago

Likewise, less wildly hypothetical but perhaps still far-reaching changes to society, such as expanding Social Security or providing universal parental leave, can’t be tested with conventional experiments that include control and experimental groups. As a result, many behavioral scientists today have instead turned to researching “nudges” — smaller interventions that operate within existing policies. Nudges can influence human behavior, research suggests, and can be readily tested using experiments before being applied.

But this recent overreliance on nudges has stifled broader behavioral science research and insights into how to create a better society, Gal and marketing expert Derek Rucker of Northwestern University in Evanston, Ill., contend January 12 in a commentary in Nature Reviews Psychology.  

Nudges exploded in popularity in 2008 when economist Richard Thaler of the University of Chicago and law professor Cass Sunstein of Harvard University published a book on the topic. That research netted Thaler a Nobel Prize in Economic Sciences and inspired governments worldwide to set up nudge units to modify or create public policies (SN: 10/9/17; SN: 3/18/17).

Examples of nudges include offering small cash rewards to encourage people to get a new vaccine or sending text reminders about a looming deadline. For instance, researchers recently revamped a court summons form and sent text reminders to get more people to attend mandatory court appointments in New York City. The intervention increased court attendance by roughly 20 percent over previous years, the researchers estimate (SN: 10/08/20).