In a new book, Against the Double Blackmail, in response to Europe’s refugee crisis, philosopher Slavoj Žižek argues that the left must shed its liberal taboos in favour of global, class solidarity. At a Guardian Live event, Gary Younge sat down with Žižek to discuss the immigration crisis, the response of the liberal left, and the future for Europe. This Guardian Live Event ook place on 19 April at the Emmanuel Centre, London

Zizek on Syriza at NYU

Sagan's lecture at Yale Peace Week on nuclear war and nuclear winter, including the TTAPS findings and proposed nuclear-arsenal reduction milestones.