The only thing I can rely on is my own perception and that is always changing.

The concept of reducibility is central to understanding the relationships between different computational problems.

文学的美在于它让我们在一生中活出千种人生。

解释：君子使自己懂得那些重大而长远的事情，小人却只注意细小的、眼前的事情。

The state, therefore, has not existed from all eternity. There have been societies that did without it, that had no notion of the state or state power. At a certain stage of economic development, which was necessarily bound up with the split of society into classes, the state became a necessity.

数学不仅仅是关于数字、方程、计算或算法：它是关于理解的。