When you're in a film that's based on a novel—I play Anne Boleyn in The Other Boleyn Girl—you want to do justice to the book and, in this case, to the character, who was a real person. To me, the story is about family rivalries but also so much about capitalism. Everyone in Tudor England buys into this system, and the girls are used to advance the family. They're commodities, but conscious commodities, because they can choose their fate. Anne goes after the goals her family and the society have set—power and wealth—whereas Mary leaves that system. Even though the sisters have limited choices, they are not confined. It's easy to think, "Well, I could do this, or I could do that." But those aren't the only two options. I think it's so interesting—how we don't have to get trapped by our own conventions. I studied psychology in school, and the best psychology is in literature. It's so much easier to understand a character than a theory. You can recognize yourself—or other people—in a different way.

Natalie Portman is the Ambassador of Hope for the Foundation for International Community Assistance, a microlending organization that helps fund women-owned businesses in developing countries.

What's on Natalie Portman's Bookshelf? Read more!