Two themes predominate [in The Idea of Justice]: economic rationality and social injustice. Mr Sen approaches them alike. He can, when he wants, theorise without oxygen at any height. But he believes that theory, to be of use, must keep its feet on the ground. Modern theorists in his view have drifted too far from the actual world.
Economists have tended to content themselves with a laughably simple picture of human motivation, rationality and well-being. People are not purely self-interested. They care for others and observe social norms. They do not always reason “instrumentally”, seeking least-cost means to given ends. They question the point of their aims and the worth of their wants. Well-being, finally, has no single measure and is not inscrutable to others. Its elements are many and do not boil down to “utility” or some cash-value equivalent.
Complexity, though, need not breed mystery. Well-being’s diverse elements (freedom from hunger, disease, indignity and discrimination, to name four) are generally observable and, he believes, measurable. They are, to put it crudely, matters of fact, not taste, even if his philosophical story—that what underpins the several elements of well-being is that they all extend people’s “capabilities”—is still argued over.
Rawls held that social justice depended on having just institutions, whereas Mr Sen thinks that good social outcomes are what matter. Strictly both could be right. The practical brunt of Mr Sen’s criticism, however, is that just institutions do not ensure social justice. You can, in addition, recognise social injustices without knowing how a perfectly fair society would arrange or justify itself. Rawlsianism, though laudable in spirit, is too theoretical, and has distracted political philosophers from corrigible ills in the actual world.