Perhaps

"Perhaps," Traveling Doctor Liu said and then shrugged. "It's a faint heartache and anger to see such a child be hurt and also a pity for the knowledge he had to be buried in history."

As a doctor, Traveling Doctor Liu was able to sympathized with the other people more easily. 

He also felt pity and sympathy for Kuang Shen.

So in the end, he chose to help this child, guided him in the way of medicine and finally taught him how to become a proper doctor. Slowly but surely, Traveling Doctor Liu allowed Kuang Shen to make his own name and grew up as a splendid doctor. 

But…

"Master, have you ever thought that not all of our personality are suitable to become a doctor?" Yu Zheng Xi asked.

"Of course I know that." Traveling Doctor Liu passed a look at Yu Zheng Xi. "Do you really think I don't know everyone's personality are different?