I think all people would like to feel that they’re a necessary part of life. That they’re necessary in the world, and that life would be poorer if they weren’t in it. When you accomplish something, when you write good poetry, then I think you feel that the world would be slightly different if you weren’t in it. And that, I think, is part of what being needed is about.
One day Joseph Lister was summoned to assist a wealthy lord with a fishbone that had lodged at the back of his throat. After Lister had skillfully removed the obstruction, the grateful patient asked him what he was owed. "My lord," Lister suggested, "suppose we settle for half of what you would be willing to give me if the bone were still lodged in your throat.