The Pythagorean discussion

How does this shift from comfort to simplicity work as a test of character, and what do you think the book is saying about what a person really needs in order to grow?
From the moment Theo wakes in a strange body and asks Where am I, where is my phone, where is my car to Pythia talk of dragons and knowing oneself, the story keeps circling around questions of identity and destiny in Chapters 2 and 3.