Incurable optimist, Dr Larry Brilliant believes that despite the many reasons for pessimism – Dafur, global warming and new infectious diseases to name but a few – human beings have always risen to the challenge.  

As a medical doctor involved in the eradication of smallpox before joining the philanthropic arm of Google and then the Skoll Foundation, Dr Brilliant’s optimism regarding poverty, disease and climate change is, er, infectious. 

His biography reads like a Hollywood movie. Trained as a doctor, he was living in a Himalayan monastery in the early 1970s when his guru told him to join the World Health Organization's smallpox eradication project. After overseeing the last case of smallpox on the planet, he went on to found the Seva Foundation which has cured more than two million people of blindness.

He continued to work with WHO in the fight to eradicate polio, set up the famous online community The WELL, became a professor of international health and, in 2006, asked the TED community to help him build a global early identification system for new diseases - a system which will be a key tool in the fight against possible pandemics like Swine Flu.

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