这是最幸运的年代,也是最倒霉的年代,这是智慧的年代,也是愚昧的年代;这个时期信仰与怀疑共存,这个时期光明与黑暗共存;这是希望之春,也是失望之冬;人们面前琳琅满目,但又一无所有;我们正直达天堂,我们正直通地狱。
The peculiar evil of silencing the expression of an opinion is that it is robbing the human race; posterity as well as the existing generation; those who dissent from the opinion, still more than those who hold it.
数学真理是普遍而永恒的。