Since the Trojan War… If I had the chance, I would invite Europeans to rediscover at least a modicum of optimism. I am aware that such an appeal may appear inopportune or even indecent in the current circumstances. We can only ask people to be optimistic when their concerns about unemployment, making ends meet, increased risks to health and so forth, have been largely dissipated. But neither should discouragement be exaggerated either. Michel Serres, a professor at Stanford and a member of...