This has been a great era for the study of error. We know that people can be induced to buy more cans of soup if you put a “Limit: 12 per customer” sign on the display. We know that if you ask people what movie they want to see next week, they’re likely to mention a classy art film. But, if you ask them what movie they want to see tonight, they’re more likely to mention a mindless blockbuster.

In addition, people are pretty bad at sacrificing short-term pleasure for long-term benefit. We’re bad at calculating risk. We’re mentally lazy. We make decision-making errors when thinking in our own language that we don’t make when thinking in another language. When asked to think in a second language, we’re forced to put in a little more mental effort.

As these cognitive biases have become better known, public spirited people naturally want to design ways to help us avoid them. In 2009, Richard H. Thaler and Cass R. Sunstein published a book, called “Nudge,” on how government and other organizations could induce people to avoid common errors. Last year, Sunstein gave the Storrs Lectures at Yale on the topic, which will soon be published as a book called “Nanny Statecraft.” Last month, the Obama administration announced that it is creating a new team to explore applications of this sort of empirical research to policy-making.

We’re entering the age of what’s been called “libertarian paternalism.” Government doesn’t tell you what to do, but it gently biases the context so that you find it easier to do things you think are in your own self-interest.