A friend is a treasure. It is a saying, maybe banal, but it is surely true. Beyond every possible consideration about this (it would be in any case evanescent and unworthy) and beyond the truth of the saying in the case of the friend I refer to (who is a real treasure chest), what I have found in the end of these days in which I have been hosted by him is a key. Keys: keys are the tool for going in and see over and more, to get over that armour door that is so often closed, inscrutable at first sight, and only known that way by those who pass through in front of it without entering.