"Despair is a black leather jacket in which everyone looks good, while hope is a frilly pink dress few dare to wear. Rebecca Solnit thinks this virtue needs to be redefined.

Here she takes to our pulpit to deliver a sermon that looks at the remarkable social changes of the past half century, the stories the mainstream media neglects and the big surprises that keep on landing.

She explores why disaster makes us behave better and why it's braver to hope than to hide behind despair's confidence and cynicism's safety.

History is not an army. It's more like a crab scuttling sideways. And we need to be brave enough to hope change is possible in order to have a chance of making it happen."