What is the meaning of this calligraphy? This slogan or motto is written in Chinese, though it comes from Korea. I have wondered many years what does it mean. Thank you for your help to understand it.



EDIT:
Thanks to the answers so far, I have found more information. Here is the University where this motto is promoted in the very old days. It remains displayed there on a small building, which maybe was at the entrance to the university in the old days.

SunKyunKwan University "Tang Pyung Be" 

There is a Korean translation there in the article, however even that is obscure to a modern Korean speaker. I think I will try a Korean translation section too. 


  周而弗比 乃君子之公心 比而不周 寔小人之私心 / 두루 사귀되 가리지 않음은 곧 군자의 공심(公心)이고, 가려 사귀되 두루치 않음은 바로 소인의 사심(私心)이다.


EDIT 2: The reply in the comment below is reasonably meaningful and thoughtful attempt of translation to English. 

"All-inclusive but not narrow-minded, this is the selflessness of the gentleman; narrow-minded but not all-inclusive, this is truly the selfishness of the petty man."

Thank you.
As far as I am concerned ,this motto is related from Lunyu which from China not from Korea . It is written by Chinese Confusius and his disciples. It's original motto is '君子周而不比，小人比而不周'. I think it is exactly similar to the motto you provide. 


List item


'周'means : coordinate;harmonize 
[That is to say the person who can in charge or  organize his members perfectly , and he can lead the team on a good way,do the good things.]
'比'means:  collude;gang with somebody  

That is to say,the motto want to tell us, the difference between 君子 and 小人 is whether he has the quality of benevolence. A person of noble character emphasize morality and justice,while 小人 only pay attention to benefit.