In science the important thing is to modify and change one's ideas as science advances.

The notion that Congress can change the meaning given a constitutional provision by the Court is subversive of the function of judicial review and it is not the less so because the Court promises to allow it only when the Constitution is moved to the left.

What is amazing for a woman of my age is that I change as the world is changing-and changing very, very fast. I don't think my mother had that opportunity to change.

We're living in an era of unprecedented change, and I want to be a part of documenting it.

Climate change was a point of division between Obama and Republican rival Mitt Romney. The president declared climate change a global threat, acknowledged that the actions of humanity were deepening the crisis, and pledged to do something about it if elected.