It is every man's obligation to put back into the world at least the equivalent of what he takes out of it.

It is every man's obligation to put back into the world at least the equivalent of what he takes out of it.

每个人都有义务把他从这个世界上得到的东西至少和他从中得到的东西相等的东西再放回到这个世界上。

-- Albert Einstein 爱因斯坦