The big threat to the planet is people: there are too many, doing too well economically and burning too much oil.

By the end of this century, climate change will reduce the human population to a few breeding pairs surviving near the Arctic.

The entire range of living matter on Earth from whales to viruses and from oaks to algae could be regarded as constituting a single living entity capable of maintaining the Earth's atmosphere to suit its overall needs and endowed with faculties and powers far beyond those of its constituent parts.

Just after World War II, this country led the world in science by every way you could measure it, yet the number of scientists was a tiny proportion of what it is now.

Climatologists are all agreed that we'd be lucky to see the end of this century without the world being a totally different place, and being 8 or 9 degrees hotter on average.

If we gave up eating beef we would have roughly 20 to 30 times more land for food than we have now.

We live at a time when emotions and feelings count more than truth, and there is a vast ignorance of science