Much of Morrie's wisdom came from careful observation of and reflection on the lives he saw around him. He lived a life filled with myriad powerful experiences as a child of the depression and also clearly a very observant child.
Because of this experiences observing patients in a mental hospital and seeing people working in horrendous conditions like his father and being unable to find work in the depression, Morrie developed the philosophy of embracing life and sucking the marrow out of its bones, experiencing it fully.
He demonstrated this attitude towards his students by giving them the same respect he gave to everyone, continuing the idea that he had something to learn from everyone and by so doing he did in fact learn from everyone.
Morrie Schwartz achieved wisdom by living every moment of his life to the fullest. He lived his life not being afraid of it and instead embraced it with every fiber of his being. He always kept a positive attitude and had a lot of life experience. He took those experiences and made life long lessons out of them. The great thing about Morrie is that he shared his wisdom with Mitch. He stressed to Mitch that he should develop his own set of values. Morrie was full of love and accepted everything as it was. He did not like popular culture and tries to teach Mitch that he needs to set himself free of all that propaganda and negativity associated with it.
Morrie was a man who looked around him and absorb it all. He was a giver to people and this entitled him to receive as much as he gave.
Morrie had spent his life teaching people to appreciate what they had and to push for what they want in life. When Mitch came back the first thing he did was ask him if he was happy with his life. Morrie was not so concerned about his own end as another's continuance.
Morrie's death brought him even further wisdom as he said he learned how to live by learning how to die.