Lewis Dartnell // The Knowledge

What if we had to rebuild human civilization from scratch — on Earth? Could you build a power plant with your own hands and some raw material? Let's start smaller: what about the printing press? We sat down with Lewis Dartnell, author of the Knowledge, to talk about our world of cascading, interrelated invention, how one might go about rebuilding it in a worst case scenario, and how to keep ours safe.