[spike2 @27
Is that a take on the "all Cretans are liars" paradox? (or "please ignore this notice, which I have once seen posted in a park!). Exam papers often had blank pages, with just the text "This page is blank" - possibly a better example.
https://en.wikipedia.org/wiki/Epimenides_paradox#:~:text=Epimenides%20was%20a%20Cretan%20who,to%20have%20spoken%20the%20truth.
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