It is only possible to come into a healthy balance, if you strive for a balance between two forces: egoism and altruism. The force that naturally arises in you is your egoism. However you are given the opportunity to balance this negative force with a positive one, so two opposing forces, called the middle line, emerges in between.
This middle line, which arises in the balance between the right (altruistic) and the left (egoistic) lines, is called human. By having a good command of both egoism and altruism, a person can interact with them correctly, constantly balancing up and down and rising on this balance. The main thing is that he learns to maintain balance. This is spiritual work.