What you don't KNOW can't hurt you
1576
Petit Palace
168
Why should I seeke to take him in it? .. So long as I know it not, it hurteth mee not.
1908
Easiest Way
III. 66
What a fellow doesn't know doesn't hurt him, and he'll love you just the same.
1979
This Fatal Writ
54
‘No, this is interesting … I didn't know—’ ‘What you don't know can't hurt you,’ said Maitland.
1984
Man in Gray Flannel Shroud
xiii.
If she weren't already aware of her dead lover's perfidy, then it was a genuine case of what you don't know can't hurt you.
1992
Rather English Marriage
(1993) vi. 115
Everyone's entitled to their privacy and what you don't know can't hurt you.
ignorance