Why are the new law students being welcomed with 允公允能 日新月异 (yǔngōngyǔnnéng rìxīnyuèyì)? The School of Law at Nankai Uni are welcoming new students with this banner:




  允公允能 日新月异 法学院欢迎各位新同学
  yǔngōngyǔnnéng rìxīnyuèyì fǎxuéyuàn huānyíng gèwèi xīn tóngxué


I think I understand the last part: 法学院欢迎各位新同学 = School of Law welcomes all new students.  But for the first part (允公允能 日新月异), I don't have much of an idea.

This is what I've found out:


允 (yǔn) = just (in the sense of justice), to permit
公 (gōng) = public
允公 (yǔngōng) = ???
能 (néng) = capable of
允能 (yǔnnéng) = ???


and


日 (rì) = day; sun
新 (xīn) = new
日新 (rìxīn) = renew
月 (yuè) = month
异 (yì) = unusual
月异 (yuèyì) = ???


(Note: the hanzi 异 looks different on the computer vs. on the banner, but this seems to be the same hanzi, see: 异 at Chinese-Tools.com)

This appears to be a poetic-style welcoming, which would explain why I can't just look it up piece by piece.

Question: Why are the new law students being welcomed with 允公允能 日新日异 (yǔngōngyǔnnéng rìxīnyuèyì)?

Google Translate gives:


  允公允能 = Allow fairness
  日新月异 = With each passing day


which doesn't mean much to me.
First of all, the welcoming sentence is 允公允能 日新月異instead of 日薪日異.
This sentence is their school motto.

允公 means that one should make himself/ herself capable of (允) thinking about the whole welfare of people (公,) and to avoid being selfish.
允能 means that one should apply (允) what he/she learns to what he/she do (能.) 能 usually means capability.

日新月異 is a Chinese proverb meaning that to learn something more everyday and to keep up with the times. 

In general, the motto is to encourage their students to keep learning, and use what they have learnt to help the society become a better place.