I was convinced that the trading frequency measured a fundamental heartbeat of financial markets. Clearly it reflected the flow of information. It turns out also to be closely related to measures of liquidity.

There are some risks we choose to take because the benefits from taking them exceed the possible costs. Optimal behavior takes risks that are worthwhile. This is the central paradigm of finance: we must take risks to achieve rewards, but not all risks are equally rewarded.

The advantage of knowing about risks is that we can change our behavior to avoid them. Of course, it is easily observed that to avoid all risks would be impossible; it might entail no flying, no driving, no walking, eating and drinking only healthy foods, and never being touched by sunshine. Even a bath could be dangerous.

My mother says that my father truly enjoyed having a son. My two-years-younger twin sisters felt that he didn't quite know how to enjoy them. But I wasn't aware of those things then. So many of my childhood memories involve him. All the excursions into science were shaped by his knowledge and enthusiasm.

At 24, I was probably making more than 95 percent of my friends. I was burning through money.

While the transition from a combustion-powered society to electrification is already underway due to market forces alone, this transition will take generations without support. But we have every incentive - environmental, economic, and yes, moral - to speed the evolution.

The three most important things a man has are, briefly, his private parts, his money, and his religious opinions.

More than ever before, there is a global understanding that long-term social, economic, and environmental development would be impossible without healthy families, communities, and countries.