Nature is actually resilient, if we take care to just stop actively destroying it.

This book [Dreams from My Father] was more of a reflection on my public life, now as a U.S. senator and before that as a state senator; how my perspectives around the issues of the day are shaped by my background.

For now, whether you are young or whether you're young at heart, I do have one final ask of you as your president, the same thing I asked when you took a chance on me eight years ago. I am asking you to believe not in my ability to bring about change, but in yours.

I'm so overexposed, I'm making Paris Hilton look like a recluse.

We should foster a culture in which people's private religious beliefs, including atheists and agnostics, are respected.

We are engaging in the diplomatic efforts that are required within Iraq among the Shia, the Sunni and the Kurd, among friends, like Egypt, and Turkey and Saudi Arabia, but also enemies like Iran and Syria. They have to have buy-in into that process.

We need scientists to design new fuels. We need farmers to help grow them. We need engineers to invent new technologies. We need entrepreneurs to sell those technologies. We need workers to operate assembly lines that hum with high-tech, zero-carbon components. We need builders to hammer into place the foundations for a clean energy age. We need diplomats and businessmen and women, and Peace Corps volunteers to help developing nations skip past the dirty phase of development and transition to sustainable sources of energy. In other words, we need you.