571: Making a Better World

Some philosophers think that morality boils down to one idea: we should make the world better for everyone. But who counts in "everyone"—babies, animals, future people? How can we tell what makes the world better for others? And in an uncertain world, how can anyone gauge the effects of their actions? Josh and Ray try to save the world with acclaimed Princeton philosopher Peter Singer, author of Ethics in the Real World: 90 Essays on Things That Matter.