Self-knowledge (n.) sees well what a man has but not what he is, which, like height above sea level, cannot be judged directly.
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Self-knowledge (n.) on film: seeing myself later in a talking picture I might say, I don't quite trust myself.
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Self-knowledge (n.) needs no evidence: another has evidence for my mental state, but I do not.
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Self-knowledge (n.) involves no doubt about one's experience, so it is wrong to say one knows it; others can doubt, and so can be certain.
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Self-knowledge (n.) is wrongly claimed as only I know what I see, but nobody says only I know whether I am colour-blind or blind.
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