I first learned about this because there's a decades-old joke in NetHack that cites this result when you ask for a major consultation from the Oracle when you c

I first learned about this because there's a decades-old joke in NetHack that cites this result when you ask for a major consultation from the Oracle when you can't afford to pay for it. I think the joke is that in this case, the Oracle can't tell you anything that's useful to you. :-)