In Plato's Apology 21a-d, Socrates reports that the Delphic oracle said no one was wiser than him. He interrogated politicians, poets and craftsmen, and concluded he was wiser only in this: he did not think he knew what he did not know. The neat formula 'I know that I know nothing' is a later paraphrase of this passage, not a quotation.
The popular version flattens the elenchus into a shrug: wisdom is admitting ignorance, end of lesson. Printed on mugs and posters, it becomes a humility badge requiring no interrogation of anyone, least of all oneself.
The structural reading: Socratic ignorance was never a confession but a weapon, the elenchus, a procedure for dissolving false certainty in others. The humility was the blade, not the sheath. Read this way the misquotation matters: it converts an aggressive technique into a passive virtue.
If the founding quote of intellectual humility is itself a misquotation, who simplified it, and what did the simplification cost?