After all, sustainability means running the global environment - Earth Inc. - like a corporation: with depreciation, amortization and maintenance accounts. In other words, keeping the asset whole, rather than undermining your natural capital.

So, what we do as individuals matters. It adds up.

I am a socialist in ideology, a capitalist in methodology.

The combination of population growth and the growth in consumption is a danger that we are not prepared for and something we will need global co-operation on.

Inertia is a powerful force in human and political affairs.

Nothing less than the fate of the planet is at stake... No place on the planet can remain an island of affluence in a sea of misery.

I am convinced the prophets of doom have to be taken seriously.