It was with great pleasure that I accepted an invitation from the Fundacion Banco Santander to lecture in Madrid. It was part of their series of lectures on The Limits of Science, organised in association with Eduardo Punset.

Last year I made two television programmes with Eduardo. You can watch the first here and the second one here.

My thanks to Fundacion Banco Santander and Eduardo for asking me to join in. You can watch a recording of the lecture here.