The millennium development goals are important, both morally and economically, because much of the world's population maybe is as much as a third of the world's population hasn't yet reached the level of economic development where we begin to get a dissociation from people's economic status and their reports about personal happiness. So we really do need to do much more and much more effectively in order to give everyone the kind of basis for which they can have good vibes.

When it comes to climate change it's all the usual barriers: greed, mendacity, ignorance, short-sightedness and so on, manifest in the extreme power of corporations, the weakness of government, and the indifference of citizens.

Our traditional systems of decision-making are just not up to preventing changes in fundamental earth systems that are driven by a constant barrage of individually negligible emissions of an invisible, odorless gas, by billions of people all over the world.

There'll come a time when airplanes are much more efficient when it comes to producing lower levels of greenhouse gas emissions, there'll come a time when we'll be able to offset those emissions much more effectively than we do now. But alas at the moment, flying airplanes is really one of the least defensible things that we do and it's one of the things that I indulge in quite frequently, alas.

I see a lot of individual action when it comes to environmental questions really as a form of politics as a way of communicating with political leaders, much in the same way that acts of civil disobedience during the civil rights' movement were really acts of political communication, trying to get laws changed rather than based on the thought that the individual action would really change the practices of segregation.

It's possible that we'll screw up the climate so badly that most of us will die and a few breeding pairs will remain somewhere in the arctic. What's more likely is that we'll continue remaking the planet, driving many species to extinction, killing millions of people through the indirect effects of climate change, making life even harder for the poor and powerless than it is now, and making it a little more difficult for the global middle class to live the lives to which they have become accustomed - in other words, business as usual, only worse.

You can't imagine anything like nature as we know it without predators.