"The universe is not about you. It's about everything."

"I'm not saying there are no aliens. I'm just saying the evidence is insufficient for me to conclude it."

"I'm a big believer in the power of curiosity. It's what drives us to explore, to discover, to learn."

"For me, I am driven by two main philosophies: know more today about the world than I knew yesterday and lessen the suffering of others. You'd be surprised how far you can get with those two."

"I'm often asked whether I believe in God. I'm an agnostic."