Every tyrant who has lived has believed in freedom--for himself.

当科学开始研究非物质现象的那一天，它将在十年内取得比过去所有世纪更多的进步。

The greatest obstacle to being heroic is the doubt whether one may not be going to prove one's self a fool; the truest heroism is to resist the doubt; and the profoundest wisdom, to know when it ought to be resisted, and when it be obeyed.

The historian's task is to resurrect the voices silenced by time.

我们有责任在应对气候变化的同时提供可靠且负担得起的能源。