"I'm coming into the prime of my career, I'm more mature than I have ever been with everything in my golf game, " said Casey, who is now based in Phoenix, Arizona.

BBC: Paul Casey aims to be English winner at Masters

We all benefit from a very mature system of our society that uses fossil fuels for virtually everything we do.

NPR: Oceanographer Sees Real Effects of Climate Change

We think we have a mature enough relationship with the Chinese that we can agree on issues that are of mutual interest, but we also have a mature enough relationship that we know that two countries on this planet are not always going to agree on everything and we'll have those disagreements.

WHITEHOUSE: Press Briefing