"I will now pause for a full two seconds to allow you to throw things at the radio", begins Adam Gopnik.

He's working hard, he claims, at a literary festival in Capri.

While there he goes in search of a white staircase - the subject of his favourite painting in the world. As he searches, he reflects on art, life and "the sketchbook of the twenty first century", the iphone.

Producer: Adele Armstrong.