Morrie's "theory of detachment" describes the way a person isolates himself/herself from the sometimes unpleasant things in life . Morrie felt in life that nothing is 'set in stone' but problems can be alleviated by transferring the negative experiences in life to positive reactions, in this case taking on the characteristics of animals or anthropomorphism. Personally, when life gives me problems that are hard to deal with I resort to prayer, thus taking on the characteristics of angels.
