一味地向前走的人路途狭窄，常常向后看的人眼界宽。

Sometimes the only way out is through.

The spread of liberal democracy around the world is not inevitable, but it is the most likely outcome of the historical process.

量子理论的发展表明，经典的空间和时间概念不足以在最基本的层面上描述物理世界。