Amartya Sen's work is situated in a general perspective of history, which for him is clearly characterized by the rise of democracy. His whole work is indeed related to the idea that only enlighten democracy can achieve justice. This article aims to show that Sen's philosophical approach is, as every political and scientific thought, a situated approach. While he claims his belonging to a tradition of “realization-focused comparative approaches” pursued in various ways by Smith, Condorcet, Wollstonecraft, Bentham, Marx or Mill, his idea of justice emerges clearly from the debates provoked John Rawls' Theory of justice. Sen's philosophy is also situated in a particular discipline: economics, and more precisely social choice theory, to which Sen dedicated his research since the early Sixties. Moreover one cannot forget that Sen is the son and grand-son of Indian intellectuals, close to the poet and philosopher Rabindranath Tagore. Thus Sen belongs to the international community of economists which implies his conforming to specific conventions and rules, but he seems to be aware that his origins have partly shaped his world vision. These particular backgrounds partly explain his influential revitalization not only of normative economics, but political philosophy as well.