I don't know the answer either; we're both equally uninformed about this matter.
This phrase emerged in American English during the early 20th century as a colloquial way to admit ignorance while suggesting that the situation is genuinely unknowable rather than reflecting personal inadequacy. It democratizes uncertainty by placing both speaker and listener on equal footing.
This phrase is a masterclass in diplomatic ignorance - it admits not knowing something while simultaneously suggesting that the information is inherently unknowable rather than just unknown to the speaker. It's a face-saving device that turns individual ignorance into shared human limitation, making uncertainty feel less embarrassing.
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