Chartres

Richard Powers, in the Goldbug Variations, attributes this story to the painter Ben Shahn: 

... an itinerant wanderer travelling over country roads in thirteenth century France comes across a man exhaustedly pushing a wheelbarrow full of rubble. He asks what the man is doing. "God only knows. I push these damn stones around from sunup to sundown, and in return they pay me barely enough to keep a roof over my head." Further down the road the traveller meets another man, just as exhausted, pushing another filled barrow. The second man says "I was out of work for a long time. My wife and children were starving. Now I have this. It's killing but I'm grateful for it ." Just before nightfall, the traveller meets a third exploited stone-hauler. When asked what he is doing, the fellow excitedly replies, "I'm building Chartres Cathedral."