The best books leave room for the reader's imagination.

数学中最重要的技能是清晰思考的能力。

I believe in the power of storytelling. It's the way we communicate, the way we understand each other.

The central task of education is to implant a will and facility for learning; it should produce not learned but learning people. The truly human society is a learning society, where grandparents, parents, and children are students together.

The only way to have a friend is to be one.