The Economics Department mourns the loss of Martin L. Weitzman. After teaching at Yale and MIT, in 1989 Marty took up a Professorship in the Department. Since his retirement in 2018, he held the position of Research Professor in the Department. (updated September 9, 2019)
Marty was a giant in the field of environmental economics. Marty’s work was broad-ranging, creative, and fundamental. His early work developed a general framework for determining when quantity regulation, or alternatively a Pigouvian tax, might be more economically efficient, and his framework remains the starting point for comparing carbon taxes and cap-and-trade systems. Recently, he focused on the challenge of climate change, a field to which he made deep and compelling contributions. These include a clear articulation of how the possibility of very bad outcomes far in the future, such as the melting of the Greenland ice sheet, provides a motivation for immediate policy action as a sort of climate insurance. He also made seminal contributions to discounting under uncertainty, to the valuation of biodiversity, and, in some of his earliest work, to the theory of centrally planned economies.
Marty had the rare ability to look at a problem in an entirely new way that led to deep, completely new insights. He was passionate about the urgency of addressing climate change, and he was an inspiration to students, colleagues and the profession. The Department will deeply miss his ideas, his warmth, his passion, and his intellectual generosity.
Remembrances from colleagues:
Marty was a true scholar and a great person. His work was legendary. There was not a field of microeconomics he did not improve. As a person, he was kind, caring, and supportive. The economics department at Harvard and the entire profession will miss him. David Cutler
My words for Marty upon his retirement. Jerry Green
My toast to Marty upon his retirement. Eric Maskin
Marty Weitzman was a treasure – a "gift that kept on giving" for both the research and policy worlds. His work as a theorist on environment broadly and on climate change in particular was unparalleled, and formed the basis of much theoretical and empirical research carried out others over several decades. In recent years, he developed strong arguments of why when analyzing the benefits and costs of proposed climate change policies it was essential to take into account the possibility of catastrophic outcomes, despite the fact that their probability might be relatively small. That changed the way economists thought about climate change policies, but it was only one of many contributions Marty made. On a personal level, I learned a tremendous amount from Marty by co-hosting with him the Harvard Seminar on Environmental Economics and Policy for 26 years -- 52 semesters including more than 400 seminars. At many sessions, his questions and comments were as informative and insightful as the speaker's presentation. I will miss him on a daily basis. Robert Stavins
Marty was an absolutely brilliant scholar—a truly original and creative thinker. But more importantly, he was a lovely person. Every interaction with him was filled with a sense of genuine personal warmth. He will be greatly missed. Jeremy Stein
As a relative newcomer to the field of environmental economics, I was tremendously fortunate to be able to learn from Marty Weitzman as a colleague. Marty cared deeply about tackling climate change; his research and thinking was driven by his desire that we must use all our tools as economists to solve this problem. In conversations as well as his research, he had a way of looking at a problem from angles that are new, unexpected, and yield deep insights. This creativity – the ability to ask the right question, then answer it with beautiful simplicity – was a hallmark of his most influential research. That research included welfare comparisons of cap-and-trade vs. carbon taxes, discounting under uncertainty into the deep future, and why possible climate catastrophes provide a motivation for climate policy action today as a kind of climate insurance. Marty’s ideas have been foundational to environmental economics in general and to climate economics in particular. Speaking personally, I was inspired by how he merged his passion for climate action with hard-headed economics. There is so much more he could have taught me, indeed that he could have taught us all. James Stock
I will really miss Marty Weitzman. Perhaps surprisingly, given that we had very different personalities, research styles and fields of interest, he was a great inspiration to me. The way in which Marty marched, usually alone, to his own drummer—pursuing questions others hadn’t conceived, reducing problems to their essence and looking as much for beauty as immediate relevance—represents the very best in the scholarly life. It wasn’t just Marty’s approach to economics that inspired me, he also had a kind of mystic brilliance that I envied. We will not see his like for a very long time. Lawrence Summers
Obituaries
Harvard University Center for the Environment, August 30, 2019
New York Times, September 4, 2019
The Economist, September 5, 2019
The Crimson, September 5, 2019