Grey's Anatomy, Season 7

Meredith:
[voiceover] When we say things like "People don't change" it drives scientists crazy. Because change is literally the only constant in all of science. Energy, matter, it's always changing. Morphing. Merging. Growing. Dying. It's the way people try not to change that's unnatural. The way we cling to what things were instead of letting them be what they are. The way we cling to old memories instead of forming new ones. The way we insist on believing, despite every scientific indication, that anything in this lifetime is permanent. Change is constant. How we experience change, that's up to us. It can feel like death, or it can feel like a second chance at life. If we open our fingers, loosen our grips, go with it, it can feel like pure adrenaline. Like at any moment we can have another chance at life. Like at any moment, we can be born all over again.