NEW YORK, NY - MARCH 21: Citi Bikes await riders at a bicycle station in Manhattan on March 21, 2014 in New York City. The leaders of Citi Bike are trying to raise millions of dollars to keep the money-losing bike-share program in business, following a severe winter which greatly reduced bicycle usage in New York City. (Photo by John Moore/Getty Images)

Co-authored with Noah Castelo

Personal decisions are the leading cause of death. This provocative claim was the result of a rigorous study demonstrating that choices we make regarding diet, smoking, drinking, exercise or lack thereof, drug use, and so on all contribute directly to a host of illnesses and accidents that can lead to death. For example, 46 percent of deaths due to heart disease and 66 percent of cancer deaths are attributable to personal decisions. And when it comes to improving our decisions, academic research and personal experience both make the resounding point that improving knowledge and understanding is not enough to create lasting change.

Though we often know what constitutes healthy behavior and strive to practice it, intentions are only weak predictors of actual behavior. Indeed, we have all been in the position of being unable to muster up the willpower to exercise or refrain from overeating despite knowing the importance of doing so.

This fact illustrates one of the defining features of being human: Though we often know what is good for us and strive to achieve it, our actual behavior often falls short of our intentions. The same goes for society at large -- we often have commonly agreed upon intentions or goals (say, minimizing health care costs) that we find unable to fulfill. An environment that could help us minimize these gaps between intentions and actions should therefore be viewed as empowering, not curtailing our autonomy. We argue, in response to Margaret Wente's recent column, that so called 'nudging' -- intentionally designing our environments to make certain decisions more likely than others -- can be an effective and ethically sound tool to help people make better decisions for themselves and for society at large.

Our argument rests on three claims. The first is the idea that governments are elected with a mandate to advance the interests of society as a whole. Though government officials do not have knowledge of the idiosyncratic preferences of every citizen, they do know that minimizing health care costs benefits society as a whole. In a country with publicly funded health care, implementing nudges that promote healthy behaviors makes everyone better off -- not just the person nudged to pick an apple over a chocolate bar. Adjudicating how "good" a decision is in terms of its effects on society thus makes it clear how decision outcomes can be improved without perfect knowledge of individual preferences.

Our second claim is that nudges do not restrict people's ability to choose, and so Wente's concerns about authoritarianism are unfounded. Though intentionally designing a cafeteria such that healthy foods are more conveniently located will lead more people to choose those foods, recent research suggests that when people have strong existing preferences, nudges have little to no effect at all. So, if you are more or less indifferent between two options, nudges can help you choose the healthier one, or the one most likely to benefit society as a whole, but if you are strongly averse to one of the options, the nudge still allows you to choose whatever you want.

Wente admits as much when she refuses to cycle in Toronto despite cycling-encouraging nudges. Nudges can thus be used to advance society-level objectives and (when they're known or self-evident) individual level intentions, without restricting anybody's freedom. We think this insight makes nudges seem much more harmless and less open to concerns about 'authoritarians' imposing their preferences on people without consent.

Finally, it is important to recognize that our environments influence our decisions regardless of how intentionally those environments were designed. The layout of a cafeteria or a grocery store inevitably makes certain food choices more likely than others. We can choose to leave these forms of 'choice architecture' to random chance, or to profit-maximizing corporations whose interests are often clearly incompatible with improving social welfare and public health. Alternatively, we can recognize that the inevitability of choice architecture provides an opportunity to improve society as a whole.