Esteemed physicist and climate policy advisor Hans Joachim Schellnhuber shares his favorite joke that brings its point all too close to home.

In the Climate Panel of the opening session of the Forum 2007, Dr. Schellnhuber reviewed the course of the talks on climate at the G8 and EU, giving us an operational metaphor for Spaceship Earth and the need to reinvent our societies.

Hans Joachim Schellnhuber is director of the Potsdam Institute for Climate Impact Research (PIK) since its foundation in 1993. He is vice chair of the German Advisory Council on Global Change and was appointed Chief Sustainability Scientist by the German Federal Government for the G8 and EU presidencies in 2007. As a member of the High Level Expert Group he also advises the President of the European Commission José Manuel Barroso on energy and climate change issues.