How do we determine the value of a life?

To protect against a possible resurgence of smallpox, the US government is funding research to improve treatments and vaccines. And since it's unethical to expose people to a highly lethal virus, labs are using monkeys as research subjects. But is it right to harm these animals to protect humanity from a potential threat? Rebecca L. Walker takes a look at this classic ethical dilemma. [Directed by Sharon Colman, narrated by Alexandra Panzer, music by Miguel d'Oliveira].