How do you know?

送交者: Latino2 于 2010-09-01, 16:44:03:

回答: JFF has left us, yili knows 由 qianfu 于 2010-09-01, 16:16:11:

引用：

There are things we know that we know. There are known unknowns. There are things that we now know we don't know. But there are also unknown unknowns. There are things we do not know we don't know.

所有跟贴:

看JFF最后一贴，及伊利的跟帖。 (无内容) - 潜伏九号 (0 bytes) 2010-09-01, 17:43:15 (482612)

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