This is a Lexicon entry: the mechanism, when it shows up, and the countermeasure. The full correction, with real-world cases and the audit prompt, hasn't been written yet.
Definition
The act of making a binding commitment now to constrain the choices available to your future self - typically because you anticipate that your future preferences will be distorted by temptation, emotion or short-term thinking. Precommitment differs subtly from commitment devices in emphasis: a commitment device is a mechanism; precommitment is the strategic act of employing one. Both exploit the insight that the self is not a single unified agent but a sequence of agents who may have conflicting interests.
When it shows up
When trying to change a behaviour that keeps reverting to default.
Failure mode
Behaviour changes that don't stick because they rely on motivation rather than identity. The person who "tries to be healthy" vs. the person who "is a healthy person."
Countermeasure
Shift from "I want to do X" to "I am the kind of person who does X." Let each action be a vote for the identity. Build the identity through small consistent actions.
Related traps
Also connected in the map4 more, locked
Credit & first seen
PopularizedDiscussed by Thomas Schelling inThe Intimate Contest for Self-Command(1980); developed in behavioural economics by Thaler, Laibson and others.
Also revealed
Entry #553 of 631 in The Lexicon · see the full Lexicon