We know that the French are very different from the Americans in their satisfaction with life. They're much less satisfied. Americans are pretty high up there, while the French are quite low - the world champions in life satisfaction are actually the Danes.

There's a very good reason for why economics developed the way it did, and that is that in many situations, the assumption that people will exploit the opportunities available to them is very plausible, and it simplifies the analysis of how markets will behave.

Each additional day together is a gift. The end of the day means the end of hostilities, the recognition that the underlying shared values and commitment to the relationship trump the need for one last dig or self-righteous justification.

When people believe a conclusion is true, they are also very likely to believe arguments that appear to support it, even when these arguments are unsound.

Most of the moments of our life - and I calculated, you know, the psychological present is said to be about three seconds long; that means that, you know, in a life there are about 600 million of them; in a month, there are about 600,000 - most of them don't leave a trace.

The concept of happiness has to be reorganised.

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