The writer's only responsibility is to his art. He will be completely ruthless if he is a good one... If a writer has to rob his mother, he will not hesitate; the "Ode on a Grecian Urn" is worth any number of old ladies.
And I hope you will come back here to Harvard 30 years from now and reflect on what you have done with your talent and your energy. I hope you will judge yourselves not on your professional accomplishments alone, but also on how well you have addressed the world's deepest inequities…on how well you treated people a world away who have nothing in common with you but their humanity.