Every life is in many days, day after day. We walk through ourselves, meeting robbers, ghosts, giants, old men, young men, wives, widows, brothers-in-love, but always meeting ourselves.

没有阴影就没有阳光，了解夜晚是必要的。

创新是唯一的出路，淘汰自己，否则竞争将淘汰我们。

The success of a learning algorithm depends on its ability to balance between fitting the data and avoiding overfitting.