所以大国攻打小国，那是互相残害，大国的错误必然反过来使其本国受害。 

自由是心灵的状态，获取它的最好方式是培育它。

数字是形式和思想的统治者，也是神祇和恶魔的原因。

The most important part of teaching is to teach what it is to know.

In the context of computational learning, the concept of 'probably approximately correct' (PAC) learning provides a framework for understanding the efficiency and feasibility of learning algorithms.