---
title: The Premack Principle
modified: 2026-06-10
tags: []
---

The Premack Principle is a behavioral psychology rule developed by psychologist David Premack.

It states that more probable behaviors can be used as rewards for less probable ones.

David Premack demonstrated the principle with experiments using children and laboratory animals. For example, if a child prefers playing to eating vegetables, Premack showed that giving the opportunity to play only after eating vegetables increases vegetable consumption.

In practice, it means you can increase the likelihood of doing a less-preferred (or [difficult](do-hard-things.md)) task by allowing access to a more-preferred activity after the less-preferred task is completed.

# How It Works

* Identify two behaviors: A (low-probability/difficult) and B (high-probability/preferred).
* Use access to B as the reward contingent on completing A: “Do A, then you may do B.”
* Because B is naturally preferred, it increases the motivation to perform A.

# Examples

* **Parenting:** “Finish homework (A) before screen time (B).”
* **Work:** “Complete this report (A) and then take a 20-minute break to check social media (B).”
* **Habit formation:** “Do 10 minutes of focused study (A), then listen to a favorite song (B).”
* **Exercise:** “Warm up set (A) before the fun part of the class (B).”

# Tips

* Keep A [small](always-start-small.md) and specific so it feels achievable.
* Use immediate, short-duration B rewards initially (immediacy strengthens reinforcement).
* Avoid making B too large or too frequent—this can overshadow intrinsic motivation for A.