In this edition of World Book Club on BBC World Service, Jostein Gaarder talks to Harriett Gilbert about his novel Sophie’s World at The House of Literature, Oslo.

A chart-topping global surprise bestseller Sophie’s World draws us into the world of the great philosophers through the intriguing character of 14-year-old Sophie and her mysterious teacher. As their relationship develops a story emerges which raises profound questions about the biggest questions of all: where we come from, the origin of the universe and the meaning of life.

The prolific and prize-winning Norwegian writer explains to a room full of his readers how amazed he was by the phenomenal success of the novel and how attached he got to his characters as he created his multi-layered tale.