"Treat the self as a story you can rewrite Reflecting on the scientific fact that half the cells in his body are not his own, Green turned an unsettling idea into a liberating one: "Self is a story that we tell ourselves and we need to make it an expansive story so that we're not stuck being the self that we were 5 or 10 or 20 years ago." Because the self is malleable rather than fixed, "my self can also change and grow," and that is "actually an encouragement." Anyone who feels trapped by an old identity — the anxious person, the failed professional, the damaged kid — can use this insight to deliberately author a more open-ended next chapter. Source: John Green, Happiness Lab / Ten Percent Happier (with Dan Harris), Everything Is Tuberculosis Episode"