John Kenneth Galbraith
1908 - 2006
I'll let Brad DeLong say it better than I could.
If there were justice in the world, John Kenneth Galbraith would rank as the twentieth century's most influential American economist. He has published several books that are among the best analyses of modern U.S. history, played a key role in midcentury policymaking, and advised more presidents and senators than would seem possible in three lifetimes.
A helpful reader informs me that the New York Times also has a long obit.
Jane Jacobs and Galbraith in one week. They say these things come in threes. We don't have many other public intellectuals of that stature to spare.