Uncommon Knowledge

In persuasion, three is the magic number

And more surprising insights from the social sciences

Time, the ethics cop

Time is money—or so they say. According to a new study, however, the two concepts push people in opposite directions when it comes to ethical behavior. People who were exposed to time-related words or concepts were significantly less likely to cheat than people who were exposed to money-related words or concepts. This effect was explained by the self-reflection that thoughts about time inspired; the researchers found that portraying a task as a test of personality, or performing a task in front of a mirror, eliminated the time-versus-money difference.

Gino, F. & Mogilner, C., “Time, Money, and Morality,” Psychological Science (forthcoming).

Hey, the government did something

Trust in government is low, making it easier for libertarians and conservatives to advocate spending cuts. What’s a liberal to do? Consider strategic transparency. In an experiment by professors at Harvard Business School, young adults in the Boston area were presented with three different views of a website that displayed neighborhood service requests to fix potholes, signs, graffiti, etc. One version displayed only the overall number of new, open, and recently closed requests; a second version also displayed on a city map the location and details of new and recently closed requests; a third version added open requests to that map. Participants then answered questions about their views of government. Those who had seen the second “partial transparency” version of the website became more supportive of big government—“equivalent to a roughly 20% decline in conservatism”—compared to those who had seen the minimalist first version. The third “full transparency” version had a political effect intermediate between the other two versions.

Buell, R. & Norton, M., “Surfacing the Submerged State with Operational Transparency in Government Services,” Harvard University (November 2013).

Fewer pictures, more memories


The next time you go sightseeing, be sure to hand off the camera periodically so you can take in the sights. In two experiments, a psychologist found that people who were directed to simply observe objects in an art museum were somewhat better at remembering those objects than people who were directed to observe and photograph the objects. However, taking a zoomed-in photograph of only a part of the object did not result in memory impairment.

Henkel, L., “Point-and-Shoot Memories: The Influence of Taking Photos on Memory for a Museum Tour,” Psychological Science (forthcoming).

Three (not four) reasons to buy this car!

If you’re in sales, marketing, matchmaking, or political consulting, you better know the magic number: three. In several experiments, people were most receptive to a sales pitch for a product—whether it was a cereal, shampoo, restaurant, date, or politician—when presented with three selling points. Beyond three, skepticism increased markedly.

Shu, S. & Carlson, K., “When Three Charms but Four Alarms: Identifying the Optimal Number of Claims in Persuasion Settings,” Journal of Marketing (forthcoming).

Kevin Lewis is an Ideas columnist.
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