A mathematician's work is never done; there are always more problems to solve.
数学家的工作永无止境；总有更多的问题需要解决。
最好的艺术既是个人的，也是普遍的。
世界不是辩证的——它誓死走向极端，而不是平衡，誓死走向激进的对抗，而不是和解或综合。
"To live is the rarest thing in the world. Most people exist, that is all."
Every child should have mud pies, grasshoppers, water bugs, tadpoles, frogs, mud turtles, elderberries, wild strawberries, acorns, chestnuts, trees to climb, brooks to wade in, water lilies, woodchucks, bats, bees, butterflies, various animals to pet, hayfields, pine-cones, rocks to roll, sand, snakes, huckleberries and hornets; and any child who has been deprived of these has been deprived of the best part of education.