任何艺术的最大问题都是创造一种存在感。

网球是一项心理游戏。每个人都很健康，每个人都能打出漂亮的正手和反手。

The key to solving complex problems is often to find the right abstraction that simplifies the problem without losing its essential features.

The only way to achieve true power is through self-mastery.

解释：使用毒性大的药物治疗疾病时，病情十成中只能去掉六成就要停药，以免伤害正气。