We simply don't know yet what's going to happen to the carbon in the atmosphere.

Science was blamed for all the horrors of World War I, just as it's blamed today for nuclear weapons and quite rightly. I mean World War I was a horrible war and it was mostly the fault of science, so that was in a way a very bad time for science, but on the other hand we were winning all these Nobel Prizes.

We cannot hope to either understand or to manage the carbon in the atmosphere unless we understand and manage the trees and the soil too.

It's clear the media, of course, always gives you the bad news. And people who rely on the media, like Mr. Trump, think that everything is a disaster. The media always tries to make everything into a disaster, but it's mostly rubbish. It's a point of fact that we're doing extremely well.

The biggest breakthrough in the next 50 years will be the discovery of extraterrestrial life. We have been searching for it for 50 years and found nothing. That proves life is rarer than we hoped, but does not prove that the universe is lifeless. We are only now developing the tools to make our searches efficient and far-reaching, as optical and radio detection and data processing move forward.

The public knows that human beings are fallible. Only people blinded by ideology fall into the trap of believing in their own infallibility.

Mathematics is really an art, not a science.