知识在心灵中以符号结构的形式表征。
数学不是一项观赏性运动。
The greatest experiments start with a simple question.
If you want to go fast, go alone. If you want to go far, go together.
The streets were dark with something more than night.
以物易物、互通有无的倾向是人类共有的,也是其他动物所没有的。
要训练一只鹰,你必须像鹰一样观察它。