ignorance is bliss
US /ˈɪɡ.nər.əns ɪz blɪs/
UK /ˈɪɡ.nər.əns ɪz blɪs/

1.
not knowing something can be better than knowing it, especially if the knowledge would cause you worry or sadness
:
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Sometimes, ignorance is bliss, especially when it comes to office gossip.
•
I didn't want to know the details of the accident; for me, ignorance is bliss.