Greeting cards exist solely because people are too lazy to write how they really feel or just plain don’t care.
贺卡的存在仅仅是因为人们懒于抒写他们真正的感受或者就只解释说不在乎。
So whether or not aliens really exist and are visiting us, many -- perhaps most -- people already think they do, and thus the claim that such knowledge is too world-changing to accept is invalidated.
所以无论是否外星人真的存在并且正在造访地球，大部分人已经认为外星人确实这样做了，因此那些关于“一旦公众知道外星人的存在就会产生世界性的改变”的论点就无法被接受了。
Unreal concepts are those that cannot refer directly to realities. They refer to other concepts and ideas which by themselves do not really exist.
非真实概念是那些不能直指真实法的概念，它们所指的是别的自身并不真实存在的概念或想法。
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