Abstract
Two cathedrals burned at the same time onApril15 2019 : the one founded in 1163 by Bishop Maurice de Sully, and the one that has been constantly reconstructed by the imagination since the 18th century. In a well-known archaeological paradox, destruction can be the prerequisite for knowledge : the scientific work that accompanies the restoration of the building thus has a revelatory effect on little-known medieval structures - , which is why the very concept of " identical restoration "is so pointless. These structures are archaeological, but they are also cultural, political and social. This is why the " cathedral of knowledge " that we have uncovered is also the one that our contemporary imaginations are building and reconstructing. By saving the past, we can measure its thickness - thatis, everything that happened between the Middle Ages and the present day.
