know is know,no know is no

问题描述:

know is know,no know is no

知之为知之,不知为不知.
论语别裁--为政第二 :
“攻乎异端,斯害也已.”子曰:由!诲,汝知之乎?知之为知之,不知为不知,是知也.
“汝知之乎?”