Nir’s Note: This guest post is by James Clear. James writes at JamesClear.com, where he share ideas for mastering personal habits. Join his free newsletter here.
In 1936, a man named Kurt Lewin wrote a simple equation that changed the way we think about habits and human behavior.
The equation makes the following statement: Behavior is a function of the Person in their Environment. 
Known today as Lewin’s Equation, this tiny expression contains most of what you need to know about building good habits, breaking bad ones, and making progress in your life.
Let’s talk about what we can learn from it and how to apply these ideas to master the habits that shape your health, happiness, and wealth.
What Drives Our Behavior?
Before Lewin’s Equation became famous, most experts believed that a person’s habits and actions were a result of the type of person they were, not the environment they were in at the time.