A few months before his death on 5 January 1910, reflecting on his entire scientific work, Walras declared that the purpose of pure economics is simply to present a rigorously rational solution to the ‘question sociale’, i.e. to the reform of society to make it ‘just’. Heir through his father from the eighteenth century French enlightenments philosophers, he strongly believed in the use of the sovereign efficiency of reason to solve both economic and social problems. He accepted neither the ‘crude empiricism’ of the Socialists bent on some romantic notion of social justice nor the individualism of the French orthodox liberal school. As early as the late 1850s, Walras was already arguing for a synthesis of collectivism and individualism (arguing maybe already for some sort of mythical ‘third way’!). This obsession with this synthesis underlines Walras’s entire work including, of course, his general equilibrium model that is only an instrument within this much larger and ambitious scheme. Hence, and not so paradoxically, general competitive equilibrium as the modern formal representation par excellence of a spontaneous market order has a largely ‘constructivist’ and normative origin.