“…Yet, in fact, the marginal cost concept underpinning the Tarif Vert owed as much to the theoretical and practical work of Maurice Allais, as it did to Dupuit. Based as Professor of Economics at I'kcole des Mines, Allais' work marked a sharp break with the Dupuit tradition by arguing against Divisia's and Roy's traditional u:se of discriminatory tariffs which, reflecting utility rather than cost, priced t:raffic according to what it could bear (Bousquet, 1947;Boiteux, 1986). In this Allais was influenced by the British economist, James Meade, whose 1936 book, Economic Analysis and Policy, arrived in France shortly before the outbreak of the Second World War.…”