Optimism is a self-fulfilling prophecy, so is pessimism. The progress we enjoy is not the result of some mysterious historical dialectic or law of inevitable progress or arc bending toward justice. It is the result of people spotting problems, including fragility and nuclear proliferation, and instead of moaning that we’re all doomed, applying their ingenuity and their efforts to solving them.

From: Do Humankind’s Best Days Lie Ahead? The Munk Debates
By: Alain de Botton   Malcolm Gladwell   Matt Ridley   Steven Pinker