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Space is not empty; it is full of possible interactions.

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.

衡量一個文明的標準是它如何對待其最弱的成員。

一個數學家的真正價值在于他們留下的問題。