Knowing this we will come to this conclusion: "Whatever has been my life's destiny, my heart through sorrow or pain, through joy or pleasure, has prepared a chemical substance that serves a certain purpose for humanity. And I can only give that chemical substance for the use of humanity if I can keep my heart awake and open." Once the heart is closed, once it is frozen, once it has turned from a warm heart into a stone, the person is no longer living. It does not matter what he has gone through, for even the worst poison can be of some use. There is no person therefore, however wicked, who is of no use, if only he knows that there is one condition for being useful to humanity, and that is to keep the heart open.