要给儿童提供一个使他们得到满足的环境，必须努力了解儿童的需要。

The beauty of mathematics lies in its ability to describe the universe in a language that is both precise and universal.

"The advantage of poetry over life is that poetry, if it is sharp enough, may last."

一本怀有恶意的书籍将不会伤害到任何人，除了写作它的傻瓜。