Ambrose Bierce: "MONUMENT, n. A structure intended to commemorate something which either needs no commemoration or cannot be commemorated.
The bones of Agammemnon are a show,
And ruined is his royal monument,
but Agammemnon's fame suffers no diminution in consequence. The monument custom has its _reductiones ad absurdum_ in monuments "to the unknown dead" -- that is to say, monuments to perpetuate the memory of those who have left no memory."