Harrod as Economist

Between the middle nineteen-twenties and the fresh outbreak of war, economic theory was transformed from its foundations. The half-century from 1870 had left in being an edifice whose symmetry, simplicity and seeming inclusiveness had gained it an unquestioned ascendancy over the liberal world. The prices, in terms of a numéraire, of all products and all means of production, the weekly quantity brought to market, and the equal quantity carried off from the market, of each product and each means, the consequent total of incomes of the suppliers of means of production, the total value, in terms of the numéraire, of everything produced in a week, and the crowning and clinching of the whole structure by a proof that those two totals, of incomes and the value of products, each total separately arrived at, were equal: all these things are shown to flow from the nature of human desires and the interaction of their resources. The conception as a whole was the Theory of General Competitive Equilibrium. It seemed by its sheer completeness and its singleness of method to be unassailable. Yet by 1926 there had begun the first of three assaults, in two of which Harrod had a central part to play.