只有我们个人对自由的信仰才能让我们保持自由。
柠檬问题是指买家无法确定产品质量,因此只愿意支付反映平均质量的价格。
The best way to predict the future is to create it.
There are some things one remembers even though they may never have happened.
志村簇的研究证明了几何直觉的力量。