This monograph grew out of a PhD dissertation, submitted to the University of Cambridge in 2018. It was titled Deus ex Machina. The Latin phrase literally means ‘God from a machine’. It described a device of ancient Greek stagecraft. At the end of a play, with the plot seemingly at an impasse, a god would descend onto the stage and solve all the problems. Apparently introduced by Aeschylus (died 456 BC), this miraculous dénouement was achieved by a crane which lowered an actor dressed as the deity. Hence ‘God from a machine’.