" I tell my students that the past is an immense ocean which we can neither sail on nor dive down into. We are stuck to our shore, which is the present. Out on the surface we can see the past of the history books, the storms and the shipwrecks, but of what happened in the far past, down in the deeps of that ocean, we have nothing to go on except the shells and bones it chooses to wash up at our feet. Why bother, then? What does it matter? It matters because that ocean is where we came from. Those seas are in our blood. "

― Peter Dickinson , A Bone From a Dry Sea