Blog post

In Giving, It Pays to Precommit

8 min read
23 Oct 2012

In Homer’s Odyssey, Odysseus’s crew sailed past the island of the Sirens. In Greek lore, the Sirens were notorious for singing a song so enchanting that those who listened would sail towards the Sirens and end up crashing into the rocks, sealing their own fate.

The common solution of the era was to avoid listening to the song altogether – plugging one’s ears with beeswax. But Odysseus wanted to listen to the song… though, of course, he didn’t want to end up crashing his ship and killing his crew.

Thus, not trusting his future willpower, Odysseus had his crew tie him to the mast of the ship and precommitted to not be let go. Predictably, when he heard the song he begged to be released, but his crew followed his earlier orders and didn’t let him go. Odysseus survived on the basis of precommitment.(1)

Why Precommitment?

The motivation for precommitment stems from a problem in human nature: there are some goals we find desirable (to know how to dance competently, to have good grades, to be fit and healthy, etc.) but still struggle to do certain activities that would accomplish these goals (take dance lessons, study hard for the upcoming test, exercise and eat right, etc.).

People are frequently averse to taking on short-term costs even if they would achieve long-term gains. (2) People value their current time much more than the future (called hyperbolic discounting),(3,4) struggle with low expectancy of success, struggle with the drudgery of actually performing the task, and are occasionally impulsive and forgetful with their tasks.(5,6)

Such failures to do what we want and act against our considered judgments are commonly called akrasia, or “weakness of will”, a term first coined by Aristotle more than two thousand years ago. Odysseus recognized that he wouldn’t have enough willpower to resist the Siren’s song, so he took steps to ensure he would end up acting the way he wanted. He used precommitment to increase his willpower.

In our own lives, we face problems where we really want to do something, but are undermined by our lack of willpower and procrastination. In looking for a solution, we can be like Odysseus… except without our lives having to be on the line. Precommitment is helpful at reducing the impulsiveness which drives procrastination and other forms of akrasia.(7) While we don’t actually have to get tied to a mast, the idea is the same – one takes an earlier and easier action now (paying for a gym membership, promising a friend, or getting tied to a pole) that makes it much easier to perform the harder yet still desirable action later on.

The Pledge to Give

Many of us think giving to charity is personally desirable. People frequently pay more for products when they’re linked to charity. The act of giving also enriches people’s lives and makes them lastingly happier. (9,10,11) However, impulsiveness means many donations are made last minute, as people forget to donate despite wanting to, and pursue giving in a haphazard and unstructured way. Just like it’s hard to eat right and exercise right, it seems hard to donate right as well.

At Giving What We Can, members take a public pledge to donate at least 10% of their income to whichever organisation they sincerely believe will do the most to help alleviate extreme poverty in the developing world. Such a pledge represents a precommitment to donate future earnings. But does it actually help people donate more than they otherwise would?

You can Take the pledge here.►

Does Precommitment Work?

In one study, smokers who wanted to quit were offered a savings account in which they could deposit a considerable amount of funds for six months. After the sixth month period, the smokers were tested for nicotine via a urine test. If they were clean, they got back all the money in their savings account. If not, all the money wasvforfeited to charity. 11% of the smokers randomly offered the program took it on – about the same rate as those that accept other smoking treatments. Of those who accepted the program, 33% were able to quit smoking, which is 3% better than other top quitting programs.

More importantly, those who were smoke-free at the end of the program were also smoke-free at a surprise follow up test six months after the first study, a year after the participants had signed-up. It seems precommitment had been able to produce lasting change in a way that other methods like financial incentives and nicotine replacements were not able to do. (12)

Along the same lines, despite some examples of people buying gym membership but never using it, a deeper examination does suggest that those people who precommit to the gym membership by paying for it in advance are more likely to go to the gym than those who express a desire but don’t get a membership. This is not just because those who would be willing to pay upfront have a stronger desire to go to the gym, those who renewed their precommitment monthly were much more likely to go to the gym than those who committed for a year. (13)

Does Precommitment Work?

Precommitment isn’t just for those who want to quit smoking or want to exercise more. Indeed, precommitment can work for those who recognize they can donate a portion of their income and benefit the world significantly, yet have trouble getting around to actually donating. In another experiment, monthly donors were randomly asked to either increase their donation immediately or precommit to increasing their donation in two months. They had not been told of the experiment. Those who were asked to precommit ended up increasing their donations on average 32% more than those who were asked to donate immediately and a year later cancellation rates were statistically identical in both groups.(14) These results were duplicated when people were asked to precommit both imaginary and real raffle winnings in separate experiments.(15)

Why does Precommitment Work?

Precommitment works well when we deliberately set things up so we cannot back out easily (backing out would be very expensive or downright impossible), but it also works even when the punishment for backing out is light. For example, backing out of a Giving What We Can pledge risks just the potential disappointment of a few people you don’t know on a personal level, or looking weird for having gone back on a public statement. So how is precommitment so powerful?

Neuroscience studies reveal that people give to charity for two primary reasons – pure altruism, or a desire to genuinely help other people, and the “warm glow” of self-satisfaction.(9,14) For many people, donating creates a tension because the pure altruism payoff is not realized for a while, but they face the prospect of parting with money immediately. By introducing a delay via precommitment, the self-satisfaction is realized immediately at the time of the precommitment, but the monetary cost (the actual donation) can be viewed with psychological distance, making us think more rationally and less impulsively about what the money can do.(3,4,5,14) Thus precommitment helps by providing the benefits upfront and costs later, which requires a type of choice, involving delayed costs, that comes more naturally to us.(2,3,4,5,14)

Additionally, precommitment creates adds a cost to backing out which, when compared with the minimal cost of complying with the precommimtent, seems not worth paying. Thus, precommiment can almost be considered “inverse procrastionation”, we procrastinate about reneging on our precommitment, even if we have changed our minds.(14)


Precommitment is a good way to reliably motivate ourselves to solve problems of impulsiveness and “weakness of will”, helping us do something we would not have otherwise been able to do. It is a weird quirk of our psychology that we have to deal with akrasia and have to “trick” ourselves into doing something we really, in the end, would have liked to have done all along. It mainly comes from our nature, for better or for worse, as impulsive hyperbolic discounters – we value the immediate present much more than the future.

Precommitment is rooted in inversing the impulsiveness and getting it to work for us, by setting up an immediate cost for not performing the long-term action. Furthermore, precommitment allows us to gain the benefits of self-satisfaction without having to immediately face its costs. Lastly, precommitment helps create the psychological distance needed to get over more automatic and immediate feelings.

Donating is one of those actions that is hard to do, especially in a structured way. But by making a public commitment to it that creates some social cost for backing out, it becomes a lot easier to keep up the habit. As most GivingWhatWeCan members can attest, skimming off the 10% of income to a top charity is not only second-nature, but fun. And all it took was a little precommitment.


1: I owe this analogy, and some of the precommitment research references, to Luke Meulhauser’s "Optimal Philanthropy for Human Beings".

2: Lowenstein, George and Richard H. Thaler. 1989. "Anomalies: Intertemporal Choice" Journal of Economic Perspectives 3 (4): 181-193.

3: Streich, Phillip and Jack S. Levy. 2007. "Time Horizons, Discounting, and Intertemporal Choice" Journal of Conflict Resolution 51 (2): 199-222.

4: Trope, Yaacov and Nira Liberman. 2003. "Temporal Construal" Psychological Review 10 (3): 403-421. American Psychological Association.

5: Steel, Piers. 2007. "The Nature of Procrastination: A Meta-Analytic and Theoretical Review of Quintessential Self-Regulatory Failure" Psychological Bulletin 133 (1): 65-94. American Psychological Assocation.

6: I owe some of the procrostination research references to Luke Muelhauser’s "How to Beat Procrastination".

7: Elfenbein, Daniel W., and Brian McManus. 2010. "A Greater Price for a Greater Good? Evidence That Consumers Pay More for Charity-Linked Products" American Economic Journal: Economic Policy 2 (2): 28–60.

8: Ariely, D. and K. Wertenbroch. "Procrastination, Deadlines, and Performance: Self-Control by Precommitment" Psychological Science 13 (3): 219-224.

9: Harbaugh, William T., Ulrich Mayr, and Daniel R. Burghart. 2007. "Neural Responses to Taxation and Voluntary Giving Reveal Motives for Charitable Donations" "Voluntary Giving Reveal Motives for Charitable Donations" Science Magazine 316: 1622-1625.

10: Ankin, Laura B.; et al. 2010. "Prosocial Spending and Well-Being: Cross-Cultural Evidence for a Psychological Universal" National Bureau of Economic Research. Working Paper #16415.

11: Dunn, Elizabeth W., Lara B. Aknin, and Michael I. Norton. 2008. "Spending Money on Others Promotes Happiness" Science 319: 1687-1688.

12: Giné, Xavier, Dean Karlan, and Jonathan Zinman. 2010 "Put Your Money Where Your Butt Is: A Commitment Contract for Smoking Cessation" American Economic Journal: Applied Economics, 2 (4): 213–35.

13: DellaVigna, Stefano and Ulrike Malmendier. 2006. "Paying Not to Go to the Gym" American Economic Review 96: 694-719.

14: Breman, Anna. 2006. "Give More Tomorrow" Stockholm School of Economics Working Paper.

15: Meyvis, Bennett, & Oppenheimer. 2010. “Precommitment to Charity” in Oppenheimer & Olivola (eds.), The Science of Giving 35-48. Psychology Press.