The past is never dead. It's not even past.

If history were taught in the form of stories, it would never be forgotten.

可持续性不是一种选择；它是农业前进的唯一道路。

I think it would be a disaster. The extraterrestrials would probably be far in advance of us. The history of advanced races meeting more primitive people on this planet is not very happy, and they were the same species. I think we should keep our heads low.