数学中最深刻的见解往往来自最抽象的理论。
The deepest insights in mathematics often come from the most abstract theories.
Hatred is the most accessible and comprehensive of all the unifying agents.
做你自己，别在意别人的看法。
"To write is to rewrite."
He who refuses to do arithmetic is doomed to talk nonsense.
"In observational studies, we often have to rely on assumptions that are not directly testable."