YOU SAID:

Real knowledge is to know the extent of one's ignorance

INTO JAPANESE

本当の知識は自分の無知の程度を知ること

BACK INTO ENGLISH

You know the ignorance of their true knowledge

INTO JAPANESE

彼らの真の知識の無知を知っています。

BACK INTO ENGLISH

Know the ignorance of the true knowledge of them.

INTO JAPANESE

それらの真の知識の無知を知っています。

BACK INTO ENGLISH

Know the ignorance of the true knowledge of them.