People often want to improve themselves. But whether it’s quitting smoking or losing weight, self-improvement is difficult. The idea for this Article came from a very real practice of its authors to make self- improvement a little bit easier. Over the course of our friendship, each of us has had personal goals related to our growth as individuals. As a way of incentivizing this development and completing these goals, we would participate in what we called “personal growth bets” with each other. These bets can, and have, dealt with any number of goals, but the canonical example is weight loss. For example, a rough outline of such a bet would be: if Max does not lose 10 pounds over the next six months, he must pay Jack $1,000. Whereas, if he does lose the weight, Jack must buy Max a steak dinner.

A vast amount of psychological research, as well as simple intuition, supports the conclusion that incentives matter. If someone knows he will either lose or make a meaningful amount of money related to a goal within his control, he is more likely to exert the effort. That does not mean incentives always work, but they have a real effect on the margins.

These personal growth bets involve three parties: (1) the aspirant, (2) the monitor, and (3) the enforcer. The aspirant seeks to achieve a certain goal but does not fully trust himself, so he tries to bind his future self with some type of present commitment to either action or inaction. For the weight loss bet, that commitment is to forfeit $1,000 if the aspirant does not lose 10 pounds. But the aspirant needs someone to monitor his future self to verify whether the commitment is satisfied (i.e., to ensure he actually loses ten pounds), and then enforce the bet if the future self fails (i.e., to ensure the $1,000 is forfeited). As will be explained below, a new technology called “smart contracts” can serve the roles of enforcer and monitor, allowing an aspirant to effectively bind his future self without the need to involve another person.

This Article argues that a personal growth bet is best described legally as a contract. These bets fit the traditional definition of a contract—legally recognized promises to act or refrain from acting in a specified way. They are not exactly “bets,” because the outcome is not uncertain in the same way most bets’ outcomes are. Like any contract, it is within the power of at least one of the parties to ensure that the bargained-for outcome occurs. These “bets” also allow a party to accomplish his ex ante goal through legal commitment, which is a defining feature of contracts.