The mind dominates your consciousness, and consciousness can dominate your behavior.
And behavior is the result of your interaction with the world.
When people meet, they can't see their hearts, only their actions.
But when you are alone with yourself, your heart is supreme.
When people meet, it doesn't matter if they have behavior or heart. But different people have different understandings of how behavior reaches the heart.
If you are willing but unable, then the existence of this person is meaningless to the people around you. The heart is the commander, which is used to control the body. The line is the army, which has no purpose, but it can influence others.