"In observational studies, we often have to rely on assumptions that are not directly testable."

For attractive lips, speak words of kindness.

简单性并不先于复杂性，而是随之而来。

城市是集体创作的艺术品。

引用俗语说明运势变化的无常性。

最伟大的发现往往来自于冒险和跳出框框思考。

爱不是胜利的进行曲，而是一声冰冷破碎的哈利路亚。