I've been a regular reader of his always-interesting New York Times columns for years, but ever since I studied his work on trade and urban geography in grad school (coincidentally, the work that would gain him the 2008 Economics Nobel Prize), I've been a huge admirer of his serious economics work as well. The Conscience of a Liberal is a response of sorts to Barry Goldwaters's highly influential 1960 book The Conscience of a Conservative, making the case that if the United States is to remain a country where everyone can pursue their own happiness in maximum liberty and peace, the Reagan-era policies that benefit the rich few at the expense of the poor many must be reversed, and a new New Deal - chiefly the establishment of universal health care - is the best way to encourage opportunity and ensure that everyone can fully participate in the ever-changing American economy. It's also an enlightening history of the modern liberal and conservative movements that does a great job of showing the direct lineage from historical states' rights segregationists to modern health care reform opponents, and how calm debate and careful thinking can and should win out over narrow self-interest and greed. A good way to tell a good book is by how much it gives you to think about after you've finished, and The Conscience of a Liberal had me thinking about it for months afterwards.
