All of his books, but above all The Sirens of Titan
The protagonist, after being dispatched to Mars and Mercury, returns to Earth as the messiah of a new religion, the Church of God the Utterly Indifferent. Expected to deliver some momentous message on arrival he responds with what becomes the central text of the Church.“I WAS THE VICTIM OF A SERIES OF ACCIDENTS, AS ARE WE ALL”. It turns out that the major structural accomplishments of earthly civilisations are not accidents, but the results of the attempt by the inhabitants of Tralfamadore, a planet in the Small Magellanic cloud, to send visible messages to a stranded pilot on Titan. Stonehenge means in Tralfamadorian ‘Replacement part being rushed with all possible speed.’The Great Wall of China means ‘Be patient .We haven’t forgotten about you’