The lie is a false narrative or perspective that the character believes about themselves or the world around them.

It has a deep-rooted connection to a past wound. The character uses the lie to explain why they are or the world is insufficient or wrong, or why they deserve to be unhappy or unfulfilled.

It is often made up of smaller lies that build into a larger mistaken view of themselves or the world and will hold them back from achieving their goals and learning to see themselves and the world as they are.

Other characters challenge the lie in order to help the character see the truth.

The lie does not allow them to weather the storms of plot and conflict. If the character clings to the lie and rejects the truth, he will fail at both his goals and will not find the answers he needs to learn.

The truth should continuously undermine the lie. This compels your character to either reject the truth (negative character arc) or reject the lie and embrace the truth to confront the final conflict and fulfill their arc of change.

The character will fall back on the lie throughout the book. It is a comfortable truth that has up to now explained reality. But growth comes only through rejecting the lie.