I can’t do Alan Krueger justice in this post. But I can say something. Much has been written about Alan’s public career. I knew him best in graduate school, and only occasionally ran into him after that.

Alan and I were classmates; we were both in Harvard’s Ph.D. program in Economics from 1983 to 1987. Alan was one of my classmates that I talked to most because we had offices close to one another: we both served as academic advisors to Harvard undergraduates in Economics while we were Ph.D. students. (As one of the perks, we got a large office shared with one other Ph.D. student instead of only getting a carrel.)

My paper “Labor-Market Dynamics When Unemployment is a Worker Discipline Device” was a direct result of Alan persuading me that Efficiency Wage Theory was important. For some years now, I have thought that a revival of Efficiency Wage Theory—and in particular, a synthesis of Efficiency Wage Theory with modern labor market search theory—would be in order. I think such a revival would be one good way to honor Alan in the course of advancing economics.

Alan had an understated manner—he wasn’t soft-spoken, but he said what he had to say in a straightforward, matter-of-fact way. Despite his influence on me, I underestimated Alan. Watching his career from afar, he became a symbol to me of how it is possible to have an enormous impact by homing in on the most important questions and being entrepreneurial in tackling those questions, without being flashy.

Because Alan focused on important questions, others often contested his answers. But that is what good science is all about: getting many people to work on the most important questions and hashing things out. Someone like Alan, who gets others to focus on the most important questions, accomplishes great good both when others confirm a result and when others show that a seeming result is wrong. And it matters. Too much of economics is either addressing minor questions or addressing big questions with tools totally inappropriate to getting a real answer to those questions. Alan addressed big questions with methods that showed a viable way forward toward an answer.

Like many others, I was totally unaware that Alan was facing the kind of inner torment that could all too often make death look like an improvement. I have been touched by suicide in the suicide of my son Spencer. (See my wife Gail’s post “The Shards of My Heart” and my daughter Diana’s posts “Every Word” and “Last Words.”) The thing I know from Spencer’s suicide is that—although there is room to regret Alan’s decision not to continue to tough it out through whatever agony he faced in order to keep doing the wonderful things he was doing for the rest of us (as he did for so long)—we are in no position to fault him for his decision to commit suicide. We haven’t walked in his shoes and can’t know how hard it was for him to make it through each day.

What I am angry about is our underinvestment in figuring out how to better treat mental health problems. Even with all of the other suffering there is in the world, I believe that suffering from mental health problems is a large part of human suffering. Without referencing his own suffering, Alan did a lot to advance the recognition of the importance of mental health problems—and more broadly, the importance of everything that contributes to a good life—with his research on subjective well-being.

In addition to direct mental health research that helps us better diagnose and effectively treat mental health problems, I hope that we are at the dawn of a general recognition that each one of us is broken in some way in relation to mental health. We each have dimensions of fragility. The greater part of wisdom is to learn well about one’s own fragilities and weaknesses and to figure out how to buttress them. And the greater part of charity is to be kind to others in their fragilities and weaknesses, even when their fragilities and weaknesses are different from our own.

Alan was a good example of how one can care about people and demonstrate one’s caring through one’s professional work. It matters what we do in the many hours every week that we work. There are very few jobs where it isn’t possible to shift one’s approach in a way that makes other people’s lives better. And fortunately, most of us have altruistic bones that make it a rare thing to make other people’s lives better without also making our own lives better.

The best way to honor Alan is to do good in the world in all the many ways it is possible to do good in the world. Alan showed us what is possible.