Detective Comics #0 Discussion between Bruce Wayne's and his Sensei.
"This Tonglen heart-practice can be very dangerous. You must see all the suffering of the world as black smoke. And you must take it in and absorb it. All the world's hatred, fear, rage... breathe it in. It is yours now. And breathe out white light. Rid yourself of your own love, compassion and joy. Give it to the world. It is honor. It is sacrifice. You must take in darkness for others who are incapable of protecting themselves from it. But. If you are not ready, this will corrupt your soul and body."
"Why must I send away from myself all that is light?"
"Light is not for you to have, Bruce-kun. It is for you to guard in others."
"Shouldn't I hold some within myself to share with others?"
"No. You must be better than others. Intimacy is a weakness. It is to be mortal, and to be mortal is to die. Love will erode your discipline. It will blind you. Guard yourself. Let no one in. Distrust everything and everyone. Only then will you become a true warrior."