“You [a disciple], shall I teach you about knowledge? What you know, you know, what you don't know, you don't know. This is true wisdom.”
Source: The Analects, Chapter II
Original
由,誨女知之乎,知之為知之,不知為不知,是知也。
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Confucius 269
Chinese teacher, editor, politician, and philosopher -551–-479 BCRelated quotes

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Source: Illusions: The Adventures of a Reluctant Messiah