What’s the worst that could happen?

We need to think, Costa says, like venture capitalists, who make a fortune despite 80% of the businesses they invest in failing; they know that 20% won’t, but not which ones. For complex problems, trying one solution and getting upset when it fails is preposterous: any single solution is likely to fail. The mindset we need isn’t the positive-thinking mantra that failure is impossible; it’s that failures are inevitable, and for good reason. It’s an unexpectedly hopeful conclusion: we may never really understand how to get what we want, or stave off the very worst – yet we may manage it anyway.