Truth

As the UK election approaches, Mark Tully seeks truth in a post-truth world. He considers how to recognise what is true among a cacophony of conjecture and, in the company of author Howard Jacobson, how fiction might lead us to truth. They agree that we live in times when the search for truth is particularly important - but more difficult than ever.

With help from the words of Mahatma Gandhi, Emily Dickinson, Joseph Goebbels and Lewis Carroll, Mark examines just how slippery the concept of truth can be, and how an untruth told often enough, with enough conviction, can become credible.

Or, as that great believer in manufactured truth, Humpty Dumpty, would have it, "when I use a word it means just what I choose it to mean."

Producer: Adam Fowler
A 7digital production for BBC Radio 4.