道，真实可信，无为且没有形相，可以流传而不可以传授，可以得到却不能够看见；自己便是本根，没有天地之前就已经存在；鬼神天帝因它而化，天地因它而生；在太极之上而不为高，在六合之下而不为深，生在天地之先而不为亘久，长于上古之时却不为老。
译文：人必须在事情上磨炼，才能立得住;才能做到安静时也安定，行动时也安定。
You think it will never happen to you, that it cannot happen to you, that you are the only person in the world to whom none of these things will ever happen, and then, one by one, they all begin to happen to you, in the same way they happen to everyone else.
数学中最重要的技能是清晰思考的能力。