Answer:
regret
Step-by-step explanation:
Valéry wrote this essay in 1919. He felt that Europe was in decline and he longed for ancient civilizations. He would like Europe to have kept her great ideas and her splendour, but he himself admitted that Europe was not free from her own destructive and changing forces.
"...Everything has not been lost, but everything has sensed that it might perish."; Valéry , through these sentences , tells that ancient civilizations were in decline , so the same would happen to Europe "...she was no longer herself,...", these words refer to the writer's feelings of regret.