But perhaps Mr. Deaton’s most important effect has been within the field of development economics, which focuses on the economies of poor countries. This is a research program born of deep personal conviction. As he recently wrote, “Those of us who were lucky enough to be born in the right countries have a moral obligation to reduce poverty and ill health in the world.”

A generation ago, development economics was a field populated by “country doctors” — globe-trotting macroeconomists willing to make house calls to any country willing to provide them with a first-class ticket, so that they could proffer their preferred prescription, be it a more muscular industrial policy, a big push of infrastructure development, increased national savings or a faster shift to a market economy. The countries varied, but the prescriptions rarely did.

Today, development economics is a far more interesting and nuanced field, with practitioners focused on understanding the lives of the poor, and in uncovering the subtle ways in which immature economic institutions hinder their development. Rather than studying a few dozen countries, modern development economists are likely to pore over data describing the economic lives of thousands of families within each country. And much of that data comes from his decades-long collaboration with the World Bank, as his work has inspired much of its recent work on measuring and assessing poverty. The result is a sharper picture of the incidence and causes of global poverty.

More recently, Mr. Deaton has turned his attention to measures of subjective well-being, including happiness. In his 2010 Presidential address to the American Economic Association, Mr. Deaton highlighted the problems in constructing coherent measures of global poverty. Measures of income don’t offer much insight unless they can be thought of in terms of differences in purchasing power. But it is impossible to assess who has more or less purchasing power when people in different countries face different prices and choose to buy different goods. Given this problem, Mr. Deaton makes the radical suggestion that economists just ask people about their well-being instead.

Many of the most important findings on subjective well-being reflect new sources of data that Mr. Deaton — together with the psychologists Ed Diener, Arthur Stone and Daniel Kahneman, a fellow Nobel laureate — have helped create through their role as a senior scientists at Gallup. (Disclosure: I also serve as a senior scientist there.)

The award for Mr. Deaton continues an extraordinary run for Princeton, whose other recent winners include the game theorist John Nash; Mr. Kahneman; the economic theorist Eric Maskin; the trade economist Paul Krugman, who is also a New York Times columnist; and the macroeconomist Chris Sims. Mr. Krugman has since moved to the City University of New York, while Mr. Maskin has returned to Harvard. Even with these departures, Princeton is close to drawing even with the University of Chicago, which still lists five economics laureates on its faculty. There’s a pretty good chance that may happen, as several of Mr. Deaton’s colleagues often feature on Nobel shortlists.

I spent a lovely year at Princeton as a visiting professor in 2012 and can attest that no one commands greater respect among his colleagues than Mr. Deaton. He’s an imposing presence, a man with a giant intellect and an extraordinary breadth of knowledge, who holds all economists to his exacting — indeed, intimidating — standards.

More than that, he’s motivated by the questions that really matter, he is intellectually relentless, he has enormous integrity and he has devoted his life to understanding and improving the lot of the poor. He’s the perfect role model for any young economist.