Arch and Resilience

An architecture professor gave us this quote during a structures seminar at the Ponts.

Once the last stone is in place (the "keystone"), an arch stands on its own. No need for nails, concrete or support. Not only does it stand, it can also carry weight. Hence this quote from Primo Levi:

"Why, I asked myself, doesn't the arch collapse, when nothing holds it up? It holds, I answered, because all the stones want to fall at the same time. This thought brought me great comfort, and I keep it with me until the decisive moment, hoping that I too will be able to hold, when everything in me wants to give way."

– Primo Levi, The Truce

An unexpected application of the stress tensor to human resilience.