A Fool's paradise is a state in which happiness is based on falsehood or foolishness.
First used in The Paston Letters (1422 - 1509), later used by William Shakespeare in Romeo and Juliet.
I can thynk and he were here he wold be a feythfull frynd
to zow ; but and so were that ze thowthe that it were for
to labore for any oder man, me thynkit it were for zow to
remembre myn nevew. That were somewat lykly, and there
to wold I be glad to help and lene to the toder. For as for
me, I know so moche that sche will none have but iff he have,
ar be leke to have, meche more lond than I have ; and iff I
knewe the contrary, it schuld nat be left for the labore, but I
wold not be in a folis paradyce, and ze be myn good brodir. I
trust thow to do rythe will.
Romeo and Juliet
Now, afore God, I am so vexed, that every part about
me quivers. Scurvy knave! Pray you, sir, a word:
and as I told you, my young lady bade me inquire you
out; what she bade me say, I will keep to myself:
but first let me tell ye, if ye should lead her into
a fool's paradise, as they say, it were a very gross
kind of behavior, as they say: for the gentlewoman
is young; and, therefore, if you should deal double
with her, truly it were an ill thing to be offered
to any gentlewoman, and very weak dealing.
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