Commitment Devices
Bryan, Karlan & Nelson
First published 2010 · review articleAnnual Review of Economics vol. 2, pp. 671–698, doi:10.1146/annurev.economics.102308.124324
What it is.
The review that defines the lever and why binding your future self works.
This is not a book. It is a review article, a paper whose job is to survey what a field found rather than add to it. A commitment device is anything you do now that limits what your future self can do later, from a locked savings account to a contract that costs money if you skip the gym. It works because the person deciding tonight and the person acting tomorrow want different things, and only one is in the room.
Working summary · based on the book itself
The strongest objection
The catch is take-up. The people who would gain most are the least likely to sign up, and the studies with the largest effects nearly all put real money on the line.
Working summary · based on Toward's records
Why it is here.
A commitment device is a choice you make now that binds your future self. You lock in a specific plan in advance and put something on the line, so backing out has a cost and showing up becomes the easier path.
The commitment principle needed a source that would tell it no. Most writing about commitment devices comes from someone selling one. This is the survey, and it is where the honest limits on the lever are stated. Toward's own tool is the soft end of that range.
Working summary · based on Toward's records
Where it sits.
Goals it serves.
Read it after Nudge. Nudge tells you commitment devices work, this tells you when. The distinction it draws between a commitment that binds you and one that only reminds you is the one most habit advice collapses.
Working summary · based on Toward's records