Peter Singer is Ira W. DeCamp Professor of Bioethics in the University Center for Human Values at Princeton University. He first became well known internationally after the publication of Animal Liberation. His other books include: Practical Ethics; The Expanding Circle; How Are We to Live? Rethinking Life and Death, One World, Pushing Time Away, The President of Good and Evil, and The Ethics of What We Eat (with Jim Mason). He co-founded The Great Ape Project with Paola Cavalieri, and is currently president of Animal Rights International. In 2005, Time named him one of the world's 100 most influential people.

Climate change raises old ethical issues in a new way. The old issues are essentially those of justice in distribution, as familiar as the old problem of sharing a pie between many hungry people. How should we divide up the capacity of our atmosphere to absorb our greenhouse gases? Justice between generations is also obviously relevant. But these issues arise in new ways that threaten our traditional sense of what is right and what is wrong. Hence climate change presents a new and particularly difficult moral challenge. [click here for video of the lecture]