You have to be able to generate usable energy without greenhouse gas emissions, and you have to be able to do it cheaply if you want people to choose that approach. That means new technologies.

We have to slow down the emissions of carbon dioxide and methane from coal burning, oil and eventually natural gas... And the best ways to do that are energy efficiency and a switch to renewables.

What we want to do is put a price on greenhouse gases. Because if they're more expensive, businesses will find a way to be more efficient or switch to solar or hydro or wind power. So that will reduce emissions.

Technology is vital. We have to have development in new technology if we're going to solve these environmental problems without throwing humanity back in poverty.

Scarcely a day goes by without some claim that new technologies are fast writing newsprint's obituary.

In the end, our minds and their ability to create new ideas are the ultimate source of all human wealth. That's a resource nearly without limit.