It is the kind of moment in history when, to summarize in the words of Alfred North Whitehead, familiar patterns fade, familiar solutions fail, and familiar options disappear.

• 我们不妨用阿尔弗雷德?诺思?怀特海德的话来加以归纳:在历史上的这种时刻，熟悉的模式在消退，熟悉的解决办法在失效，熟悉的选择在消失。