Conserving energy and thus saving money, reducing consumption of unnecessary products and packaging and shifting to a clean-energy economy would likely hurt the bottom line of polluting industries, but would undoubtedly have positive effects for most of us.

With an estimated population of nine billion people by 2050, we cannot continue to consume resources at the same rate and maintain our quality of life.

I can't imagine anything more important than air, water, soil, energy and biodiversity. These are the things that keep us alive.

People.. especially people in positions of power.. have invested a tremendous amount of effort and time to get to where they are. They really don't want to hear that we're on the wrong path, that we've got to shift gears and start thinking differently.

Global trade has advantages. For starters, it allows those of us who live through winter to eat fresh produce year-round. And it provides economic benefits to farmers who grow that food.

Any scientist who tells you they know that GMOs are safe and not to worry about it, is either ignorant of the history of science or is deliberately lying. Nobody knows what the long-term effect will be.

Rapid population growth and technological innovation, combined with our lack of understanding about how the natural systems of which we are a part work, have created a mess.