At least since Socrates, philosophers have been interested … (Of course, Socrates was concerned not about knowledge … ).  In various dialogues, the Platonic Socrates gradually … [Plato, Republic, V.474B-480; Cratylus, 440; Meno, 97; Gorgias, 454; Timaeus, 28; Theaetetus, 202].  It is eternal and must continue to abide and exist … rather than persuasion or propaganda; it is able … must be true.  
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