Catharsis is the purging of emotions or the alleviation of emotional tensions. Metamorphosis is change of form or substance. Catharsis should lead to metamorphosis if the alleviation of emotions or the eradication of emotional tensions is followed up by action. That action should naturally lead to change within once your inner tension has been released. When you purge emotions, you are releasing hormones AND stuck energy. Catharis begins a spiritual process that MOVES energy for your improvement. You can change your own substance by catharsis followed by metamorphosis. Until I relieve myself of emotional tension, I can't see the path ahead. That path needs actions to define where you're going to go, and how you're going to do things differently. Metamorphosis will eventually come if you remain open.