Start the Week - Creativity: Jonah Lehrer

On Start the Week Andrew Marr discusses creativity with the writer Jonah Lehrer. In his latest book, Imagine, Lehrer unpicks the creative process in both science and art, to ask where inventiveness and imagination spring from, and how they can be harnessed. Experimental sound artist, Scanner, talks about creating unique musical compositions and his latest collaboration with the Heritage Orchestra at the Brighton Festival; and the novelist Joanna Kavenna considers the importance of nourishing creative ideas in writing fiction. She argues that everyone is born creative, although as we get older this innate imaginative ability is often suppressed or side-lined. Finally, the chemist, Rachel O'Reilly, explains the importance of the creative process in scientific research and how blue-sky thinking aids developments in nano-materials and technology.

Producer: Katy Hickman.

More or Less: Behind the Stats - The formula that changed the world

The Midas Formula - In this week's More or Less: The story of Black-Scholes, the equation that transformed Wall Street ? and the arguments over whether it made the world a better place, or helped cause the financial mess we have all been dealing with for the past five years. This programme was first broadcast on the BBC World Service.