Maybe an asteroid hit Earth. Perhaps a nuclear war reduced our cities to radioactive rubble. Or an avian flu killed almost everyone on Earth. However it happened, the world as we know it is over and we must start again. So how do we set about rebuilding our world from scratch?

In this Ri event, Lewis Dartnell takes us, the survivors, by the hand as we reconnect with the basic skills and knowledge which our lives and world depend upon. How do you grow food and make clothes? Or generate energy and develop medicines? We are taken on a journey of rediscovery that transforms our understanding of the world.

'The Knowledge: How to Rebuild our World from Scratch" is out now with Bodley Head. Thumbnail credit: the-knowledge.org

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