Willpower

from hearing or seeing certain Web sites. A modern Stanley can use the Web in the same way that the explorer used the social media of his day. In Stanley’s private letters, newspaper dispatches, and public declarations, he repeatedly promised to reach his goals and to behave honorably—and he knew, once he became famous, that any failure would make headlines. Having piously lectured his men about the perils of drunkenness and the need to shun sexual temptations in Africa, he knew how conspicuous his own lapses would be. By creating the public persona of himself as Bula Matari, the unyielding Breaker of Rocks, he forced himself to live up to it. As a result of his oaths and his image, Jeal said, “Stanley made it impossible in advance to fail through weakness of will.”
    Today you don’t need to be famous to worry about ruining your image with a lapse in willpower. You can precommit yourself to virtue by using social-networking tools that will expose your sins, like the “Public Humiliation Diet” followed by a writer named Drew Magary. He vowed to weigh himself every day and promptly reveal the results on Twitter—which he did, and lost sixty pounds in five months. If you’d rather put someone else in charge of the humiliation, you could install software from Covenant Eyes that will track your Web browsing and then e-mail a list of the sites you visit to anyone you designate in advance—like, say, your boss or your spouse. Or you could sign a “Commitment Contract” with stickK.com , a company founded by two Yale economists, Ian Ayres and Dean Karlan, and a graduate student, Jordan Goldberg. It allows you to pick any goal you want—lose weight, stop biting your nails, use fewer fossil fuels, stop calling an ex—along with a penalty that will be imposed automatically if you don’t reach it. You can monitor yourself or pick a referee to report on your success or failure. The penalty might simply be a round of e-mails from stickK.com to your designated list of supporters—friends and relatives, generally, although you could choose some enemies, too. But you can also make it financially costly by setting up an automatic payment from your credit card to charity. For an extra incentive, you can assign the payment to an “anticharity,” which is a group you’d hate to support—like, say, the presidential library of either Bill Clinton or George W. Bush. Not surprisingly, stickK.com ’s users seem to be motivated by financial stakes (just as Stanley was—he knew he had to come up with stories to sell newspapers and books) and by the presence of a referee. People who draw up a contract without a financial penalty or a referee succeed only 35 percent of the time, whereas the ones with a penalty and a ref succeed nearly 80 percent of the time, and the ones who risk more than one hundred dollars do better than those who risk less than twenty dollars—at least according to what is reported to stickK .com, which doesn’t independently verify the results. The true success rate is presumably lower because some referees are reluctant to report failures that would hurt their friends financially. And whatever the success rate, this is obviously a self-selected sample of people already motivated to change, so it’s hard to know exactly how much difference the stickK.com contracts make. But the efficacy of contracts with monitors and penalties has been independently demonstrated in a more rigorous offline experiment, conducted by Karlan and other economists, among more than two thousand smokers in the Philippines who said they wanted to quit.
    The economists randomly offered some of these Philippine smokers a commitment contract with a bank, which would give them a weekly opportunity to make a deposit into an account paying no interest. It was suggested that the smokers deposit the amount of money ordinarily spent on cigarettes, but the level was strictly voluntary—each week they could deposit as much as they wanted, or nothing at all (and many of the smokers ended up depositing nothing). At the end of six months, the people would submit to a urine test. If the test found any nicotine in their body, they’d forfeit all the money in the account (which the bank would donate to charity). From a strictly financial standpoint, it was hardly an ideal investment strategy for the smokers who accepted the contract. They could have guaranteed themselves a better return simply by putting the money into a regular