be living in a fool's paradise

To be in a happy state for foolish, unfounded, or delusional reasons. We were living in a fool's paradise thinking that the financial successes of the early 2000s would last forever. Does she really think she can protect her kids from every negative thing in life? If so, she's living in a fool's paradise! Now that I live on my own and cover all of my expenses, I know I was in a fools' paradise when I thought this job paid well!

be living in a fool's paradise

If someone is living in a fool's paradise, they believe wrongly that their situation is good, when really it is not. Anyone who believes that this deal heralds a golden new era for the European air traveller is living in a fool's paradise. Note: You can also use a fool's paradise on its own to mean a situation where someone thinks things are good, but really they are not. Mrs Deedes looks much happier. But surely hers is a fool's paradise.