For amateur golfers, I think one of the biggest mistakes is to model their play on professionals.

If you're trading individual securities, you're almost certainly making a mistake. Because most professional managers can't outperform their benchmarks, and there's little reason to think that individuals can.

Countries all around the world, starting with the U.K., have started behavioural insight teams, often referred to as nudge units. And they seem to be doing lots of good.

There can be legal conflicts over whether registering intent is enough to qualify you as an organ donor or whether a doctor must still ask your family's permission.

Countries that are agricultural can, at a low standard of living, sustain themselves. You can be self-sufficient; the money economy is a relatively insignificant part of the total economy. Singapore never was an agricultural country.

In countries with a properly functioning legal system, the mob continues to exist, but it is rarely called upon to mete out capital punishment. The right to take human life belongs to the state. Not so in societies where weak courts and poor law enforcement are combined with intractable structural injustices.

My home life, growing up, was like tumbling inside a washing machine as I shuttled around the middle of Kentucky with my mother. She was never content to stay in one place, or with one man, for too long. She was as smart as she was independent, though, and always landed some job that brought in a little money.

What's the use of happiness? It can't buy you money.