If we don’t change, we don’t grow. If we don’t grow, we aren’t really living.

Sheehy links personal vitality to continual adaptation. The first sentence treats change not as disruption but as the necessary condition for development; resisting it stalls the self. The second sentence raises the stakes: without growth, “living” becomes mere existence—routine, static, and unexamined—rather than an active process of becoming. Read in light of Sheehy’s broader themes about adult life transitions, the line affirms that identity is not fixed; it is revised through new roles, losses, ambitions, and reinventions. The quote functions as both diagnosis (stagnation is a kind of non-life) and exhortation (embrace change as the engine of meaning).