Free Thinking: A Pinch of Salt

Matthew Sweet looks at today's world with 'a pinch of salt' in this edition. From stories in the Bible to desalination plants, preserving food to salt taxes, how does salt help people think about the past and present? Everyday phrases are explored, including 'being worth your salt' or 'dropping salt'. With food writer Bee Wilson, materials scientist Mark Miodownik and artist David Soin Tappeser