The main environmental challenge of the 21st century is poverty. When you don't know where your next meal is coming from, it's hard to consider the environment 100 years down the line.

The 21st century simply means open century.

The great challenge of the twenty-first century is to raise people everywhere to a decent standard of living while preserving as much of the rest of life as possible.

If we invest in researching and developing energy technology, we'll do some real good in the long run, rather than just making ourselves feel good today. But climate change is not the only challenge of the 21st century, and for many other global problems we have low-cost, durable solutions.

It's important to move the theatre into the 21st Century.

It's the 21st century. It's healthier for us, better for the environment and certainly kinder to be a vegetarian.