Denshi Jisho — Online Japanese dictionary

無知 むち ignorance; innocence; stupidity
Common word, Na-adjective, Noun 
無知の知 むちのち wisdom to realize one's own ignorance
Noun 
無知愚昧 むちぐまい unenlightened; in the darkest ignorance; not knowing from A to B
Noun, Na-adjective 
無知蒙昧 むちもうまい unenlightened; in the darkest ignorance
Na-adjective, Noun 
無知文盲 むちもんもう ignorant and illiterate
Noun, Na-adjective, Sensitive 
無知は幸福 むちはこうふく Ignorance is bliss
Expression, Idiomatic expression 

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