This is a powerful concept, and something I believe is a key motivation for a lot of strange behaviors.
Our brains need us to constantly reaffirm our sense of self (the ego), lest we should enter psychosis or become unable to differentiate ourselves from the “other.” Our sense of
identity is critical to how we behave, what we believe, and how we see the world.
This is one of the few forces more powerful than
Habits in terms of affecting our behavior, and as such if you want to change a bad habit, you should try to re-align your identity first. Ex: “I am someone who doesn’t bit their nails”.