A saint doesn't have to be as gentle as Confucius, but he has to know manners so rigidly. You can laugh, you can cry, you can be angry, but you should never lose your heart.
Why is Joan of Arc called a "saint"? That's because even though she was betrayed by her own people, she was brutally abused and eventually burned alive. But even so, she still believed in her own affairs and left the last piece of pure land in her heart. That's why they are called saints.
Saints are not pure white, but full of contradictions and inner struggles. Even after countless pains and despair! People call someone a saint, because he has profound thoughts, and because people see his strength from the pain of his life!
Finally, Harvard. Although Harvard is the best school, it is only a school after all. Even if it can impart all kinds of knowledge taught by ancestors, even so, those students lack the quality of becoming saints because they have not experienced painful training. Saints are not cultivated by themselves, but given by heaven. So schools can't teach saints.