The tumblehome
Chestnut brand canoes dominated the Canadian wilderness for years. One reason is that they were shaped with a tumblehome. If you leaned the boat over, the boat leaned back, providing stability. The more you leaned, the harder the boat worked to stay upright.
This is the resilience that leads to stability, not brittleness. It is the hallmark of a system that is aware of the forces on it and responds with just enough to keep things steady over time.
Tumblehome provides support, but it also requires ongoing effort, care and focus to keep a system functioning. The tumblehome doesn’t take care of itself.
Every existing system persists because it has a sort of tumblehome. And if you want to understand a system, it helps to see where the tumblehome lies.