There is a process in ecology called succession — the orderly advance of ecosystems from one state to another. There are moments of terror and unfathomable destruction, and then stability returns and life takes hold again, often with a firmer grip. This applies, of course, both to nature and to human society. As Jane Jacobs wrote, “Lively, diverse, intense cities contain the seeds of their own regeneration.” Resilience is a hallmark of any successful system, whether for a forest, a wetland or a city.