A scene from the Hay Festival, 2011 © Sarah Barton
From judgement to atonement: sculpture at Strasbourg, Lincoln and Naumburg
Paul Crossley, Courtauld Institute
University of York, King’s Manor, York, 5.30pm, free, 01904 322622,
Is democracy right for the world’s current problems?
Andrew Gamble, David Runciman and Glen Rangwala, University of Cambridge
Hay Festival, Big Tent, Hay-on-Wye, 1pm, £5.25, 01497 822629,
Does the sun cause climate change?
Lucie Green, solar scientist; Mark Maslin, paleoclimatologist
Cheltenham Science Festival, Town Hall, Imperial Square, Cheltenham, 12.45pm, £7, 08448 808094,
Abolitionist experimentation in Sierra Leone: conflicting ideas and expectations
Suzanne Schwarz, WISE
Hull History Centre, Worship St, Hull, 12.30pm, free, 01482 305176,
Thomas Friedman: a manifesto for rescuing America
Thomas Friedman, columnist and author
The Royal Institution, 21 Albemarle St, W1, 7pm, £25, 020 7792 4830,