There is a huge wave of interest in happiness among researchers. There is a lot of happiness coaching. Everybody would like to make people happier.

Mental effort, I would argue, is relatively rare. Most of the time we coast.

Friends are sometimes a big help when they share your feelings. In the context of decisions, the friends who will serve you best are those who understand your feelings but are not overly impressed by them.

Our memory tells us stories, that is, what we get to keep from our experiences is a story.

However, optimism is highly valued, socially and in the market; people and firms reward the providers of dangerously misleading information more than they reward truth tellers. One of the lessons of the financial crisis that led to the Great Recession is that there are periods in which competition, among experts and among organizations, creates powerful forces that favor a collective blindness to risk and uncertainty.

After a crisis we tell ourselves we understand why it happened and maintain the illusion that the world is understandable. In fact, we should accept the world is incomprehensible much of the time.

It's a wonderful thing to be optimistic. It keeps you healthy and it keeps you resilient.