我们期望晚餐不是出自屠夫、啤酒商或面包师的仁慈,而是出自他们对自身利益的考虑。
It is not from the benevolence of the butcher, the brewer, or the baker that we expect our dinner, but from their regard to their own interest.
每个数学问题都有一个解决方案;只是需要时间和努力去找到它。
世界是一个伟大的花园,我们是其中的花朵。