Ego, in this book, does not mean confidence or self-respect. It means the belief that I am fundamentally separate — from other people, from the living world, from consequence.
That belief is useful. It lets a person defend a boundary, hold a position, take responsibility for a body. It becomes destructive when it hardens into the operating assumption of a whole life — and catastrophic when it becomes the operating assumption of an economy.
Ego does not announce itself. It rarely appears as arrogance; it prefers subtler costumes. It hides in the need to be understood, in the maintenance of an image, in spiritual pride — I have seen further than these people — and in the long private story of grievance in which one is always the one to whom things happen. It survives on comparison, on control, and on the fear of becoming invisible.
At civilisational scale the same structure appears as externality: the accounting convention by which the cost of an action is placed outside the boundary of the actor. A river downstream, a generation not yet born, a species with no representative in the negotiation. Every externality is a formalised claim of separateness. The atmosphere does not honour the claim, which is why the accounting eventually fails.