Justin Brierley is joined by Jonathan Hill, author of "The Big Questions". The book tackles some of the biggest philosophical questions to do with the existence of God, free-will and faith. What can we learn from the way Christians down the ages have attempted to answer these questions? With guests Tim Mawson of Oxford University and Jim Paul of the L'Abri fellowship in Hampshire.

To hear more discussions between Christians and non-Christians go to www.premier.org.uk/unbelievable.