Resilience is a wonderful metaphor. It somehow conveys in a single word the qualities of bending without breaking, of healing after an injury, of tensile rather than brittle strength. Oak and palm trees are resilient to the power of strong winds, before which they bend and then straighten again. Resilient people pick themselves up after being knocked down, draw on their reserves of ideas and strength to deal with difficult challenges, or hunker down until the gale has blown itself away. Resilient economies bounce back, and resilient ecosystems restore themselves after the fire or the flood has passed.