In curbing runaway climate change, humanity is predictably succeeding at what it does best – technological innovation – and failing at what it does worst – reaching difficult political agreements. The question is whether the successes of the former will outweigh the failures of the latter. The answer is that the odds have improved, but they are still not good enough. There is now less doubt that technology will prevail in time. That was not the case two decades ago. But the combination of technological innovation with learning by doing has led to huge reductions in the cost of renewable energy. Solar and wind are increasingly competitive with conventional fuels. An energy system based on clean electricity is now conceivable. (MARTIN WOLF, Financial Times)