Preface

This book has been a long time coming. In graduate school, many years ago, I was inspired by the crystalline version of libertarianism articulated in Robert Nozick’s 1974 book Anarchy, State, and Utopia – inspired, that is, to show why this view was dead wrong. My dissertation argued that libertarianism rests on an undefended and indefensible distinction between “negative” duties not to harm and “positive” duties to aid, and in turn between action and omission. I wouldn’t put the point quite this way today, but the animating idea persists as one of the main themes of this book. In the course of writing my dissertation I was lucky to meet Henry Shue, whose book Basic Rights: Subsistence, Affluence, and U.S. Foreign Policy was soon to appear. Henry’s work helped push my thinking further along.

I continued to think and write about these questions over the years while working on other projects. But the plan to write a book took shape only much later. Like many other moral philosophers over the last decades, I was interested in the question “What are the moral responsibilities of comfortable people to alleviate poverty?” But I became convinced that to decide what people ought to do, we need to know what it is reasonable to expect them to do, which requires an understanding of human motivation and behavior. Defending this idea and exploring its implications have been the central themes of this book.